Post hard problems and solve them.

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Anonymous Sat Mar 9 01:44:21 2019 No.10450178 [Reply] [Original]

Post hard problems and solve them.

>>	Anonymous Sat Mar 9 01:46:47 2019 No.10450183 >>10450178 time to get a watch

>>	Anonymous Sat Mar 9 01:48:51 2019 No.10450188 6:53

>>	Anonymous Sat Mar 9 01:51:34 2019 No.10450195 >>10450178 >literal arithmetic progression omg my brain cannot handle this difficulty

>>	Anonymous Sat Mar 9 01:54:10 2019 No.10450200 >>10450178 ? = 7:05 Second watch = first - 12 3rd = 2nd - 24 4th = 3rd - 36 ? = 4th - 48 y = 9:05 - x (watch) * 12 (consider the first watch as the 0th watch) Took 2 minutes I consider myself bad at maths

>>	Anonymous Sat Mar 9 01:54:12 2019 No.10450201 File: 56 KB, 1080x259, 4.png [View same] [iqdb] [saucenao] [google] >>10450178 It's an arithmetic progression, 5th grade level of difficulty. The answer sums up to 12. Here's one from a book literally called "Problems for children from 5 to 15".

>>	Anonymous Sat Mar 9 01:57:17 2019 No.10450206 >>10450201 too hard for this board

>>	Anonymous Sat Mar 9 02:01:34 2019 No.10450214 File: 35 KB, 870x489, maxresdefault (1)_0.jpg [View same] [iqdb] [saucenao] [google] >>10450178 7:05

>>	Anonymous Sat Mar 9 02:03:13 2019 No.10450217 >>10450214 110

>>	Anonymous Sat Mar 9 02:03:29 2019 No.10450220 >>10450201 8

>>	Anonymous Sat Mar 9 02:04:53 2019 No.10450222 >>10450214 81

>>	Anonymous Sat Mar 9 02:05:04 2019 No.10450223 >>10450220 Did you just add up cm with mm?

>>	Anonymous Sat Mar 9 02:05:46 2019 No.10450224 >>10450214 101

>>	Anonymous Sat Mar 9 02:06:43 2019 No.10450227 guys what are numbers and how do you combine them I'm in over my head here

>>	Anonymous Sat Mar 9 02:06:48 2019 No.10450228 >>10450223 ya, i'm the guy who makes stupid mistakes on tests

>>	Anonymous Sat Mar 9 02:08:29 2019 No.10450231 >>10450188 >>10450195 >>10450200 >>10450201 You brainlets, this is a normative question about what the watch should show, so the answer is it should show the current local time

>>	Anonymous Sat Mar 9 02:10:13 2019 No.10450233 >>10450228 Well, try again, it's not a test. And you leveled up your attentiveness stat (hopefully). >>10450231 I didn't want to spoil the answer because it really is very easy, so I just posted the sum of the numbers.

>>	Anonymous Sat Mar 9 02:10:22 2019 No.10450234 >>10450201 44mm

>>	Anonymous Sat Mar 9 02:10:30 2019 No.10450235 >>10450178 7:05

>>	Anonymous Sat Mar 9 02:11:04 2019 No.10450238 File: 34 KB, 640x360, totally legal.jpg [View same] [iqdb] [saucenao] [google] >>10450178 the answer is 4:20

>>	Anonymous Sat Mar 9 02:11:13 2019 No.10450239 >>10450214 20 + 20 + 20 = 60 answer / number of flowers = 20 20 + 5 + 5 = 30 (answe - red flower) / 2 = 5 5 - 2 * 1 (pair of yellow) = 3 (blue - answer) / 2 = 1 1 + 20 * 5 = 101 (single yellow + red + blue) = 101

>>	Anonymous Sat Mar 9 02:13:39 2019 No.10450244 >>10450234 You would think so, but then it wouldn't be as fun of a book, so no! Try to picture it.

>>	Anonymous Sat Mar 9 02:14:48 2019 No.10450246 >>10450201 Dont know what perpendicular means

>>	Anonymous Sat Mar 9 02:15:30 2019 No.10450250 >>10450239 please note the amount of petals the blue flower has on the bottom row

>>	Anonymous Sat Mar 9 02:16:07 2019 No.10450251 >>10450178 7:05

>>	Anonymous Sat Mar 9 02:21:20 2019 No.10450254 File: 18 KB, 282x290, perpendicular_slope_2.jpg [View same] [iqdb] [saucenao] [google] >>10450246 Orthogonal, at a right angle, at an agle of 90 degrees.

Anonymous Sat Mar 9 02:21:46 2019 No.10450255 [DELETED]

>>10450214
[math] \displaystyle
\left \{ \begin{matrix}
x+x+x &= 60 & \Leftrightarrow x=60/3=20 \\
x + y + y &= 30 & \Leftrightarrow y=(30-20)/2=5 \\
y-2z &= 3 & \Leftrightarrow z=(5-3)/2 =1
\end{matrix} \right.
\\
z+x \cdot y = 1+20 \cdot 5 = 101
[/math]

Anonymous Sat Mar 9 02:25:34 2019 No.10450261

>>10450214
[math] \displaystyle
\left \{ \begin{matrix}
x+x+x &= 60 & \Leftrightarrow x=60/3=20 \\
x + y + y &= 30 & \Rightarrow y=(30-20)/2=5 \\
y-2z &= 3 & \Rightarrow z=(5-3)/2 =1
\end{matrix} \right.
\\
z+x \cdot (y-1) = 1+20 \cdot (5-1) = 81
[/math]

>>	Anonymous Sat Mar 9 02:27:04 2019 No.10450267 File: 671 KB, 1485x993, Albert and Bernard.jpg [View same] [iqdb] [saucenao] [google] heh...heh

>>	Anonymous Sat Mar 9 02:28:47 2019 No.10450270 >>10450201 46mm? Surely the bookworm couldn't have started inside the first volume.

>>	Anonymous Sat Mar 9 02:29:04 2019 No.10450271 >>10450267 fuck this, never even understood the explanation

>>	Anonymous Sat Mar 9 02:31:19 2019 No.10450273 >>10450201 4.2cm

>>	Anonymous Sat Mar 9 02:34:33 2019 No.10450278 >>10450178 7:05 time to smd

>>	Anonymous Sat Mar 9 02:34:41 2019 No.10450279 >>10450254 So they just intersect like the x and y axis on a grid?

>>	Anonymous Sat Mar 9 02:36:47 2019 No.10450284 >>10450250 I always miss one thing, and that one thing always fucks me over In tests for example

>>	Anonymous Sat Mar 9 02:37:32 2019 No.10450285 >>10450178 The set of possible answers has cardinality [math]\aleph_1[/math], retard.

>>	Anonymous Sat Mar 9 02:38:34 2019 No.10450288 >>10450267 July 16, also I missed the word "respectively" at first and wasted my time solving a pointlessly harder problem. Also wtf is Cheryl's game here anyway

>>	Anonymous Sat Mar 9 02:40:45 2019 No.10450292 >>10450267 June 17

>>	Anonymous Sat Mar 9 02:46:06 2019 No.10450303 File: 70 KB, 540x218, too hard for sci.png [View same] [iqdb] [saucenao] [google]

>>	Anonymous Sat Mar 9 02:48:53 2019 No.10450310 >>10450303 Obviously 11, it's this sequence https://oeis.org/A006005 ezpz

>>	Anonymous Sat Mar 9 02:49:55 2019 No.10450312 File: 416 KB, 540x1080, told you.png [View same] [iqdb] [saucenao] [google] >>10450310 Based retard.

>>	Anonymous Sat Mar 9 02:54:33 2019 No.10450320 File: 1.30 MB, 1485x2097, Albert and Bernard solved.jpg [View same] [iqdb] [saucenao] [google] >>10450267 >>10450292 posting solution

>>	Anonymous Sat Mar 9 02:54:34 2019 No.10450319 >>10450270 >>10450273 No, anons, draw a picture and pay attention to the order of the books. >>10450279 Yes, the worm goes along x-axis while the books stand along the y-axis. >>10450267 The answer is the Bastille Day.

>>	Anonymous Sat Mar 9 02:54:36 2019 No.10450321 >>10450267 what? i can only get it down to three solutions how does albert know after bernard? bernard narrows it down between those three with his number, but how did albert get it?

>>	Anonymous Sat Mar 9 02:56:16 2019 No.10450324 File: 1.47 MB, 1485x993, 1552116424551.png [View same] [iqdb] [saucenao] [google] >>10450267 July 16

>>	Anonymous Sat Mar 9 02:57:48 2019 No.10450327 >>10450319 >The answer is the Bastille Day. Then how does Bernard know it's not August 14, you fool

>>	Anonymous Sat Mar 9 02:59:23 2019 No.10450332 >>10450320 please explain the second step

>>	Anonymous Sat Mar 9 02:59:26 2019 No.10450333 >>10450320 fuck me, i frazzled my brain

>>	Anonymous Sat Mar 9 03:01:04 2019 No.10450337 >>10450332 If Bernard's given number was 14, he wouldn't have enough information to know when her birthday was because July and August both have 14.

>>	Anonymous Sat Mar 9 03:02:52 2019 No.10450346 >>10450337 I mean the one above that the first step I guess

>>	Anonymous Sat Mar 9 03:04:57 2019 No.10450350 >>10450324 but how did albert figure it out himself?

>>	Anonymous Sat Mar 9 03:05:21 2019 No.10450351 File: 20 KB, 380x481, basado y rojopillado.png [View same] [iqdb] [saucenao] [google] >>10450178 5:45.

>>	Anonymous Sat Mar 9 03:06:01 2019 No.10450353 >>10450201 43mm

Anonymous Sat Mar 9 03:06:02 2019 No.10450355
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>>10450327
I am a fool, I got the answer (pic related) and forgot to get the date from the "Actual date" column. I encouraged other anons to be more attentive to problems while I myself failed to be so. Interesting problem, thanks!

>>	Anonymous Sat Mar 9 03:08:17 2019 No.10450359 >>10450346 Albert knows it isn't may or june, that's why he knows Bernard doesn't know the answer. Bernard is intelligent enough to understand this clue and crosses off both may and june

>>	Anonymous Sat Mar 9 03:10:59 2019 No.10450367 >>10450346 See >>10450324 If Albert knows Bernard doesn't know, then each day in the month Albert knows must share a day with other months. This means Albert's month isn't May or June. Otherwise, if it was 18 or 19, Bernard would have a chance to know.

>>	Anonymous Sat Mar 9 03:11:20 2019 No.10450368 File: 36 KB, 296x276, full_NvvNtIgN.jpg [View same] [iqdb] [saucenao] [google] >>10450353 >>10450273 >>10450270 >>10450234 >>10450201 Alright guys, posting the clue that will undoubtedly give you the answer - 4mm.

>>	Anonymous Sat Mar 9 03:12:55 2019 No.10450370 >>10450350 Because he knows the month is July, and the only option left is 16.

>>	Anonymous Sat Mar 9 03:13:52 2019 No.10450372 >>10450359 >>10450367 thanks I get it now time to sleep :DD

>>	Anonymous Sat Mar 9 03:14:09 2019 No.10450374 >>10450368 i'm done, this stuff killing me

Anonymous Sat Mar 9 03:15:08 2019 No.10450376
File: 51 KB, 900x208, 73.png [View same] [iqdb] [saucenao] [google]

By the way, here's a link to the book "Problems for children from 5 to 15":
https://imaginary.org/sites/default/files/taskbook_arnold_en_0.pdf

The worm/book problem was one of the easiest, they get progressively more hardcore towards the end (pic related).

>>	Anonymous Sat Mar 9 03:17:59 2019 No.10450380 >>10450376 Not gonna lie, I would have had some difficulty with number 73 at age five. I guess I'm not gonna make it

>>	Anonymous Sat Mar 9 03:19:54 2019 No.10450384 >>10450370 ugh, now i feel retarded

>>	Anonymous Sat Mar 9 03:25:43 2019 No.10450389 >>10450368 4mm because the first page of volume 1 is in the middle of the picture. The clue helped.

>>	Anonymous Sat Mar 9 03:31:25 2019 No.10450398 File: 54 KB, 813x208, Screen Shot 2019-03-09 at 3.29.31 AM.png [View same] [iqdb] [saucenao] [google] I like this one. (Answer is less than 30)

>>	Anonymous Sat Mar 9 03:32:19 2019 No.10450400 File: 113 KB, 1200x960, 1526275103364.jpg [View same] [iqdb] [saucenao] [google]

>>	Anonymous Sat Mar 9 03:39:19 2019 No.10450418 >>10450398 Wtf is this, I'm russian and I think it's 30

>>	Anonymous Sat Mar 9 03:43:31 2019 No.10450423 >>10450418 Read the problem carefully. If you still don't get it, draw it.

>>	Anonymous Sat Mar 9 03:49:49 2019 No.10450431 File: 15 KB, 500x500, wut.jpg [View same] [iqdb] [saucenao] [google] >>10450423 I don't get it :(

>>	Anonymous Sat Mar 9 03:51:51 2019 No.10450435 >>10450431 it must be a confusion over the word "altitude" in Russian the way I interpreted it the 6 was how tall the side of the triangle was

>>	Anonymous Sat Mar 9 03:54:18 2019 No.10450437 File: 3 KB, 213x156, file.png [View same] [iqdb] [saucenao] [google] >>10450435 Seems the moral of the story is that Americans don't know geometry terminology, then.

>>	Anonymous Sat Mar 9 03:55:01 2019 No.10450438 >>10450435 I'm fluent in english though and it seems to me like "altitude dropped onto it (the hypotenuse)" is completely unambiguous. Neither of the sides of the triangle is an altitude onto the hypotenuse, by definition

>>	Anonymous Sat Mar 9 03:56:56 2019 No.10450440 >>10450437 altitude is usually how tall something is I guess it's how you orient your triangle, so maybe Russians usually draw their triangles with hypotenuse downward, and Americans draw it with the right angle in the lower right or lower left

>>	Anonymous Sat Mar 9 03:58:15 2019 No.10450446 >>10450440 >altitude is usually how tall something is Not in geometry, and that's not a russian thing. https://en.wikipedia.org/wiki/Altitude_(triangle)

>>	Anonymous Sat Mar 9 04:09:26 2019 No.10450471 >>10450437 The moral is that the you don’t use the hypotenuse for calculating area. American students have the Pythagorean Theorem drilled into their heads so they find the base using that and then do 1/2 base times height.

Anonymous Sat Mar 9 04:10:48 2019 No.10450474

>>10450398
>>10450418
>>10450423
>>10450431
>>10450437
>>10450438
>>10450440
>>10450446
I think Arnold implied that American students mindlessly used the formula while in reality such triangle cannot exist, as the maximum altitude is only 5 inches for the given hypotenuse.

>>	Anonymous Sat Mar 9 04:13:15 2019 No.10450479 >>10450471 >implying russian students don't know or use the pythagorean theorem I'm still waiting for a coherent explanation of why the answer isn't 30, under the assumption that Arnold hasn't gone insane

>>	Anonymous Sat Mar 9 04:13:45 2019 No.10450483 >>10450474 See >>10450471 t. American

>>	Anonymous Sat Mar 9 04:16:09 2019 No.10450490 >>10450479 Hypotenuse is 10. One edge of triangle is 6. 6^2 + x^2 = 10^2 x = 8 Other edge is 8. 1/2 * 6 * 8 = 24

>>	Anonymous Sat Mar 9 04:17:06 2019 No.10450492 >>10450479 You cannot have a triangle as shown in this picture >>10450431

Anonymous Sat Mar 9 04:17:15 2019 No.10450493

>>10450490
>One edge of triangle is 6.
But that's literally wrong. This isn't a language issue, it's a matter of the universally accepted definition of the geometric term "altitude". Neither of the sides of the triangle is an altitude, because they are not perpendicular to the hypotenuse.

>>	Anonymous Sat Mar 9 04:21:18 2019 No.10450500 >>10450474 >>10450492 Hadn't thought of that, I guess I've been Arnold'd. But what is he implying the Americans did here? It's madness

>>	Anonymous Sat Mar 9 04:23:02 2019 No.10450504 >>10450493 Then it shows Americans aren’t properly taught what “altitude” means and the problem becomes impossible, he was then implying the Americans said 30 and as a result my answer is wrong.

Anonymous Sat Mar 9 04:25:15 2019 No.10450509

It's easy to see what altitude values are possible for a fixed hypotenuse. Draw a circle with the hypothenuse as the diameter. By a well-known property, any point on the circle will form a right triangle with the hypothenuse. But then any altitude will at max be half the length of the hypothenuse (5 inches).

>>	Anonymous Sat Mar 9 04:36:14 2019 No.10450516 >>10450214 105

>>	Anonymous Sat Mar 9 04:39:33 2019 No.10450521 >>10450504 Oh shit it really was a language issue, I thought his "(giving 30 square inches as the answer)" referred to the russians. Lmao fuck you Arnold, learn to write an unambiguous sentence

Anonymous Sat Mar 9 04:46:30 2019 No.10450530
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>>10450521
To be fair, the original is less ambiguous, and he did not translate this himself. I'm not sure whether he was fluent in English, but he lived and taught in France for a long time.

>>	Anonymous Sat Mar 9 04:49:40 2019 No.10450533 >>10450530 Ok my apologies to Arnold, it really is a based question after all and I'm just a brainlet

>>	Anonymous Sat Mar 9 05:01:22 2019 No.10450551 >>10450398 >>10450504 So now that that's all settled, can a topologist or geometer or whoever come up with a solution in non-Euclidean geometry?

>>	Anonymous Sat Mar 9 10:40:51 2019 No.10451150 >>10450351 What website is this?

>>	Anonymous Sat Mar 9 11:36:21 2019 No.10451276 >>10450178 7:05

>>	Anonymous Sat Mar 9 12:34:26 2019 No.10451399 >>10450178 8:39

>>	Anonymous Sat Mar 9 12:51:45 2019 No.10451444 >>10450201 4 mm?

>>	Anonymous Sat Mar 9 12:54:00 2019 No.10451450 >>10450178 bout tree fiddy

>>	Anonymous Sat Mar 9 13:03:20 2019 No.10451466 >>10450398 how is his not 1/2 b*h = 30?

>>	Anonymous Sat Mar 9 13:06:35 2019 No.10451474 >>10451466 oh it's an ambiguous sentence, Americans got 30

>>	Anonymous Sat Mar 9 13:08:12 2019 No.10451483 File: 206 KB, 780x772, Autism+tests_ec5046_5668465.jpg [View same] [iqdb] [saucenao] [google]

Anonymous Sat Mar 9 13:34:50 2019 No.10451560

>>10450231
>what the watch should show, so the answer is it should show the current local time
What if I want it to show something else?
When I was a teen I used to have a watch that was 5 minutes ahead, so every time I looked at it I would get a little scare about being too late and hurry up, before remembering that it's wrong?

Anonymous Sat Mar 9 13:54:24 2019 No.10451609

>>10451483
impossible as k3,3 is nonplanar.

Proof: bipartite implies triangle free. in particular each face has degree 4 or more.

Sum over face degrees to obtain 4f <= 2e, hence f <= e/2. Substitue into v-e+f=2 to obtain e<=2v - 4. k3,3 has 9 <= 8, contradiction.

>>	Anonymous Sat Mar 9 13:59:24 2019 No.10451625 File: 1.12 MB, 320x240, 1279759825744.gif [View same] [iqdb] [saucenao] [google] >>10451483

>>	Anonymous Sat Mar 9 14:01:42 2019 No.10451628 File: 7 KB, 271x71, sum.png [View same] [iqdb] [saucenao] [google]

>>	Anonymous Sat Mar 9 14:03:09 2019 No.10451633 >>10450231 Why would you expect the last watch to show the current time when all but maybe 1 out of the other 4 watches don't?

>>	Anonymous Sat Mar 9 14:04:31 2019 No.10451637 File: 237 KB, 780x772, 1552154892828.jpg [View same] [iqdb] [saucenao] [google] >>10451483

>>	Anonymous Sat Mar 9 14:05:11 2019 No.10451639 File: 102 KB, 1601x797, brainlet-filter.png [View same] [iqdb] [saucenao] [google] >post hard problems >ITT: not hard problems

>>	Anonymous Sat Mar 9 14:06:21 2019 No.10451641 >>10450398 It’s 24

>>	Anonymous Sat Mar 9 14:06:23 2019 No.10451642 File: 39 KB, 644x500, brainlet.jpg [View same] [iqdb] [saucenao] [google] >>10450201 >tfw to stupid to understand kiddo problems

Anonymous Sat Mar 9 14:09:50 2019 No.10451653 [DELETED]

>>10450509
You could also observe:
1) The altitude divides the triangle into two right triangles, with the legs of the large right triangle as their hypotenuses.
2) Each of these hypotenuses has length greaster than either of their legs, so greater than 6.
3) The altitude divides the hypotenuse.
4) Therefore one of the smaller right triangles has legs of length 6 and less than or equal to 5 and a hypotenuse greater than 6, a contradiction.

>>	Anonymous Sat Mar 9 14:13:58 2019 No.10451658 File: 998 KB, 780x772, asdf.png [View same] [iqdb] [saucenao] [google] >>10451483 easy

>>	Anonymous Sat Mar 9 14:15:45 2019 No.10451661 >>10451639 don't expect any of these retards to try your problem.

>>	Anonymous Sat Mar 9 14:16:35 2019 No.10451662 >>10451639 cause people don't want to spend too much time on bullshit like you posted

>>	Anonymous Sat Mar 9 14:19:26 2019 No.10451665 >>10451661 > He says without trying it himself Welcome to the club, helmets are mandatory and remember to never talk to strangers. mkay.

>>	Anonymous Sat Mar 9 14:21:44 2019 No.10451668 File: 1.40 MB, 4602x3852, 1492387279385.jpg [View same] [iqdb] [saucenao] [google] >>10451662 >plz gibme hard problemz leik the facebook memes we posted >>10451665 I'm fucking working on it.

>>	Anonymous Sat Mar 9 14:21:56 2019 No.10451669 >>10451658 you crossed houses for that one red line, that is a foul

>>	Anonymous Sat Mar 9 14:24:14 2019 No.10451674 >>10451669 >setting arbitrary boundaries

>>	Anonymous Sat Mar 9 14:25:06 2019 No.10451677 >>10450261 oh yes that sneaky 4 leaf flower

>>	Anonymous Sat Mar 9 14:28:04 2019 No.10451691 File: 241 KB, 780x772, 1552154892828.jpg [View same] [iqdb] [saucenao] [google] >>10451674 nigga if you can do that then you can do this

>>	Anonymous Sat Mar 9 14:31:32 2019 No.10451698 File: 240 KB, 780x772, 1552154892828.jpg [View same] [iqdb] [saucenao] [google] >>10451674 or even this

>>	Anonymous Sat Mar 9 14:33:31 2019 No.10451706 File: 239 KB, 780x772, 1552154892828.jpg [View same] [iqdb] [saucenao] [google] >>10451674 and might as well just do this, cause then all that matters is the lines are touching the houses without each other

>>	Anonymous Sat Mar 9 14:34:18 2019 No.10451707 >>10450324 i've never seen anything as retarded as this. shove it up your ass cunt

>>	Anonymous Sat Mar 9 14:36:29 2019 No.10451714 >>10451706 Are you fucking blind? The other anon simply avoided the house's boundary by skillfully navigating the gap.

>>	Anonymous Sat Mar 9 14:38:23 2019 No.10451719 >>10450201 Since there are 4 different ways the books can be standing next to each other side by side, the bookworm will gnaw through 2,4cm per layout.

>>	Anonymous Sat Mar 9 14:38:30 2019 No.10451720 >>10450201 48mm 2mm cover - 2 cm pages - 2mm cover - 2mm cover - 2cm pages - 2mm cover Come on /sci/, I used to have respect for you

>>	Anonymous Sat Mar 9 14:43:34 2019 No.10451733 >>10451714 are you dumb as shit? i've had a similiar problem in a classroom setting. there is no solution, thats why its an autism test cause anons "solve" an unsolvable problem

Anonymous Sat Mar 9 14:44:40 2019 No.10451738

>>10450178
I have one. A problem from a Russian math textbook for classes 7-11

Three people have come across a pile of immeasurable goods (imagine sand or something). There are no scales, no rulers, nothing that can be used to measure the goods. How do they proceed to divide it so that each is happy and no one thinks they got an unfair share?

I'm aware there can be numerous solutions, we can debate which one is best once you bring them forth. I will post the original solution in 30 minutes.

>>	Anonymous Sat Mar 9 14:46:23 2019 No.10451740 >>10451714 https://en.wikipedia.org/wiki/Three_utilities_problem#Solution

>>	Anonymous Sat Mar 9 15:00:09 2019 No.10451776 File: 142 KB, 1024x954, 1552135819797.jpg [View same] [iqdb] [saucenao] [google] >>10451483 from >>1045070

>>	Anonymous Sat Mar 9 15:01:32 2019 No.10451779 >>10451776 I meant >>10450701

Anonymous Sat Mar 9 15:24:20 2019 No.10451843

>>10451738
Solution:

First, they arbitrary decide an order (the order doesn't really matter, but they can flip a coin or pull sticks, whatever). Person 1 takes the amount he deems he would be happy with. He asks person 2 if he agrees with him taking that share. If person 2 disagrees, he gets to take the share person 1 had taken out of the pile. If person 2 agrees, person 1 asks person 3. If person 3 disagrees, he gets the share person 1 had taken. After this, one person has gotten his share (and he is certainly content).

Then, two people remain. Following the same predetermined order, no matter which of the three fell out (let's say person 2 fell out in our example), person 1 takes what would be enough to make him happy. He asks person 3 if he agrees with him taking what he selected out. If person 3 agrees, person 1 gets what he took and person 3 gets the rest. If person 3 disagrees, he gets what person 1 had taken out for himself.

This way, everyone is sure to be happy. Of course, this presumes neither two conspire against the third.

Anonymous Sat Mar 9 15:51:50 2019 No.10451898

>>10450271
You basically read between the lines and just eliminate all impossible candidates on each step

Step 1:
There are exactly 2 dates where the day is enough to determine the birthday: May 19 and June 18.
If the date would be on one of those days, Bernard would be certain of the date.
Albert saying that Bernard certainly doesn't know the date already implies it is NOT on either May or June since Albert can only guess this by month.

Step 2:
Since Bernard now knows that it is only on July or August, his date is enough to get the birthday. This means that his date must be unique between those two months. Which means only July 16, August 15 and August 17 come in question.

Step 3:
Albert now knowing the birthday implies that it can be the only candidate in his month, so it must be July 16, since he couldn't be certain if it was on August

>>	Anonymous Sat Mar 9 16:02:22 2019 No.10451914 >>10450201 >>10450368 Oh FUCK this question come ON.

>>	Anonymous Sat Mar 9 16:18:23 2019 No.10451936 >>10450178 ok, assuming the watches belong to a repeating set of 4, we can conclude the last watch should be 9:05 because it's the 1st entry of the next set pretty easy

>>	Anonymous Sat Mar 9 16:24:59 2019 No.10451949 File: 3.10 MB, 3664x2844, 1552134074979.jpg [View same] [iqdb] [saucenao] [google] >>10451779 this is my favorite one

>>	Anonymous Sat Mar 9 16:28:46 2019 No.10451952 >>10451560 That means you are an ubermensch who creates his own normative values

>>	Anonymous Sat Mar 9 17:05:55 2019 No.10452055 >>10450267 This reminds mes of a joke. Three logicians walk into a bar. The bartender asks "Would you three like a beer?" The first logician says "Maybe." The second logician says "Probably." The third logician says "Yes."

>>	Anonymous Sat Mar 9 17:07:32 2019 No.10452063 >>10451609 This nigga failed

>>	Anonymous Sat Mar 9 17:14:39 2019 No.10452084 File: 269 KB, 780x772, 1552154892828_solved.jpg [View same] [iqdb] [saucenao] [google] >>10451483

>>	Anonymous Sat Mar 9 17:22:57 2019 No.10452120 >>10452063 >>10452084

>>	Anonymous Sat Mar 9 17:30:51 2019 No.10452150 File: 36 KB, 968x1132, 1551338906258.png [View same] [iqdb] [saucenao] [google] more than a year since we conquered 33-40

>>	Anonymous Sat Mar 9 17:41:41 2019 No.10452192 >>10451150 I used Wolfram for the cubic regression of (1,905), (2,853), (3,829), and (4,753) and plotted the resulting function in GeoGebra.

>>	Anonymous Sat Mar 9 17:54:10 2019 No.10452236 >>10451633 The question doesn't ask what it shows, it asks what it should show

>>	Anonymous Sat Mar 9 18:15:33 2019 No.10452309 >>10451720 I want you to take 2 books. Label them 1 and 2. Put 1 on a shelf and then 2 next to it. Open 1 up and note where page 1 is. Put it back. Open 2 up and see where the last page is. Put it back. Rethink your answer.

>>	Anonymous Sat Mar 9 18:18:52 2019 No.10452320 >>10451843 This is genius.

>>	Anonymous Sat Mar 9 19:13:54 2019 No.10452455 >>10450400 How do you do this one without knowing what the perimeter segments are?

>>	Anonymous Sat Mar 9 19:51:00 2019 No.10452517 >>10451843 What if person 2 takes person 1's choice in the first step but person 3 wants it? Doesn't person 2 need to offer the switch also? This solution in general makes a lot of assumptions about person 1's strategy in dividing the piles

>>	Anonymous Sat Mar 9 22:14:10 2019 No.10452834 >>10450400 28

Anonymous Sun Mar 10 03:01:43 2019 No.10453219

>>10452517
Person 1 has no incentive to take more or less than 1/3. If he chooses more than 1/3 he will likely end up with less. If he chooses less than 1/3 he will end up with that. Unless the other two people are complete retards/ afraid of person 1.

>>	Anonymous Sun Mar 10 03:20:49 2019 No.10453270 >>10451898 ty, saved I'll go over it a 1000 times, maybe it'll punch thru this time

>>	Anonymous Sun Mar 10 03:40:07 2019 No.10453303 File: 1 KB, 110x125, 1547846931470s.jpg [View same] [iqdb] [saucenao] [google] >>10452309 <--This is how I feel The crux was in the part I barely read. Thank you anon.

>>	Anonymous Sun Mar 10 03:43:54 2019 No.10453317 >>10452517 Yes I think person 2 asking person 3 whether or not he wants the pile would be an improving addition to the solution. That way, I think that there would be no way for anyone to be left out even if two people conspired against the third.

s Sun Mar 10 10:54:44 2019 No.10453903

>>10452517
What about selecting two people so each one makes one cut in the pile of goods. Then we have three different amounts, to prevent that any of them would be bigger than the others we set that the thirth one (who didn't make a cut) chooses the cut who he likes most, surely would be the bigger one if there is such a difference between the cuts. THen he would pick of the remaining two cuts and selects the one he would take as his second best choice. This cut would be given to one od the two people who made the cut earlier, and would be decided by tossing a coin.

>>	Anonymous Sun Mar 10 10:58:32 2019 No.10453913 >>10453903 What would you do if you could build muscle?

>>	Anonymous Sun Mar 10 11:02:40 2019 No.10453921 >>10453913 I'd conquer the world and savagely murder everybody to replace mankind's genetics with only my own (this should be the goal of every man ever)

>>	Anonymous Sun Mar 10 11:52:00 2019 No.10454003 File: 30 KB, 800x600, maths lol.png [View same] [iqdb] [saucenao] [google] >>10451661 >>10451662 it seems either unsolvable or way too tedious for my tastes

>>	Anonymous Sun Mar 10 11:56:11 2019 No.10454010 File: 39 KB, 800x600, more maths lol.png [View same] [iqdb] [saucenao] [google] >>10454003 at this point we start getting complications

>>	Anonymous Sun Mar 10 14:01:54 2019 No.10454313 >>10451628 sqrt(e) Try this [math]\lim\limits_{n\rightarrow\infty}\prod\limits_{k=-n}^n(1+{1 \over n+ik})[/math]

>>	Anonymous Sun Mar 10 14:30:39 2019 No.10454380 >>10453219 right but that's the thing. this solution presupposes perfect rational behavior (and no collusion) which is totally unrealistic. In the real world, person 1 would probably take less than his fair share and be unhappy.

>>	Anonymous Sun Mar 10 15:09:28 2019 No.10454488 File: 2 KB, 204x81, fix.png [View same] [iqdb] [saucenao] [google] >>10454003 >>10454010 fix

>>	Anonymous Sun Mar 10 15:13:45 2019 No.10454499 >>10454380 >this solution presupposes perfect rational behavior (and no collusion) which is totally unrealistic. Isn't that all game theory?

>>	Anonymous Sun Mar 10 15:56:16 2019 No.10454610 >>10454488 oh good, that makes things so much better

>>	Anonymous Sun Mar 10 16:03:17 2019 No.10454635 >>10454488 if ur the bullshitmaker, pls tell me if that funny A symbol is really the square root of 21

>>	Anonymous Sun Mar 10 16:14:50 2019 No.10454667 >>10454488 this thing is bulshit, there are like 4 multiplications here that make prime numbers or don't make wholes

Anonymous Sun Mar 10 16:17:24 2019 No.10454675

>>10451738
Each person makes one wish, and three objects are pulled from the pile to grant those wishes. The rest is given back to the nothingness, since there is always a default rule, scale, and measure, in a cybernetic metaversal context.

That is, if we live in a simulation, the best thing to do is let lost objects return to their bearer.

Your assumptions don't hold otherwise, because you implied reality was real.

Never assume reality is real.

Anonymous Sun Mar 10 16:26:55 2019 No.10454702

>>10453317
Search the pile for the object that seems most likely to summon The Fairy Queen. Use that to (attempt) to summon her. If that fails, take 100 items from the pile (doesn't matter the order). Each player selects the item they think is most likely to summon a fairy they already have any sort of familiarity with. If possible, they can try to use an anonymous lottery that they know is rigged in their favor to get the item they want, without stealing the items of the other fairies.

When each player has contact their fairy, the rest of the pile can be divided up by the fourth party, after which a pirate convention selects to invent a fifth, new party, that has never existed before in the entire history of the metaverse. This ensures scalar parity, and makes Queen not have any reason to turn black.

If, by chance, you should happen to stumble upon a pile of darkness, infinite in measure, and it seems like you might want to take the thing you desire most.

Don't.

Anonymous Sun Mar 10 16:29:08 2019 No.10454707

>>10454499
Why would a pirate care about game theory? He has a space ship.

Oh wait.

Were we NOT willing to assume this gathering was able to be simulated, and retrocausally punished via time travel?

Because why would you ever assume that? Is "illusion" magic not just 'simulation' by another name?

Because it is now.

>>	Anonymous Sun Mar 10 18:00:46 2019 No.10454943 File: 50 KB, 1578x842, squire.png [View same] [iqdb] [saucenao] [google] >>10450400 pls explain the best i can gt is the unknown area = 4*x^2 - 68cm^2, where x is half the side length

>>	Anonymous Sun Mar 10 18:50:59 2019 No.10455086 >>10450178 Whatever the current time is.

>>	Anonymous Sun Mar 10 21:16:23 2019 No.10455505 >>10450201 YES BASED ARNOLD POSTER Here's another one from that collection: you walk 10 miles south, 10 miles east, shoot a bear, then finally another 10 miles north and find yourself back at your original location. What colour was the bear?

Anonymous Sun Mar 10 21:32:08 2019 No.10455537

>>10450376
oh hm poincare recurrence!
i dont recall details, but i remember the physical interpretation (which, surely, arnold would approve of)

our bounded domain M is a phase space, and our initial open set U is some volume of it. Since the volume it sweeps out under repeated applications of g is finite, some copies of the images must intersect: g^m(U) \cap g^n(U) nonempty for some m,n.

But for that piece of volume to pass from its initial starting point, to g^m, to g^n, then back to g^m, it must intersect its preimage in U by smoothness at some point between g^m and g^n. We can then do the same thing where we replace U by that intersection to get arbitrarily large periods of recurrence.

>>	Anonymous Sun Mar 10 21:41:22 2019 No.10455556 >>10454667 it's a thread for hard problems suck it up

>>	Anonymous Sun Mar 10 22:39:08 2019 No.10455674 File: 14 KB, 500x550, StruggleBus.png [View same] [iqdb] [saucenao] [google] >>10454943

Anonymous Mon Mar 11 06:28:26 2019 No.10456340

>>10455556
It's not a hard problem you bellend, it's an impossible problem made to look like it might be solvable. The square root of 21 Isn't a whole number, unless we're looking at a non base 10 numerical system, in which case how the fuck does one figure out what that base is?

>>	Anonymous Mon Mar 11 09:21:11 2019 No.10456500 >>10450214 102

>>	Anonymous Mon Mar 11 09:47:34 2019 No.10456534 >>10450398 a^2 + b^2 = 10^2 a + b = 10 also c * h / 2 = 30 which means a * b = 30 a + b = 10 and a * b = 30 which is impossible https://www.wolframalpha.com/input/?i=a+%2B+b+%3D+10;+a*b+%3D+30

>>	Anonymous Mon Mar 11 09:48:36 2019 No.10456538 >>10456534 yeah im a retard....

Anonymous Mon Mar 11 09:51:38 2019 No.10456544

>>10456538
>>10456534
i meant
a^2 + b^2 = 10^2
sqrt(a^2 + b^2) = 10

also
c * h / 2 = 30
which means
a * b = 30

sqrt(a^2 + b^2) = 10
and
a * b = 30
which is possible
https://www.wolframalpha.com/input/?i=sqrt(a%5E2+%2B+b%5E2)+%3D+10;+a*b+%3D+30
im confused now

>>	Anonymous Mon Mar 11 09:53:05 2019 No.10456548 >>10456544 ok im spamming at this point, apparently i got confused about the pythagorean theorem.... for some reason i put in the square root. first reply this one >>10456534 is the correct one... triangle is impossible

>>	Anonymous Mon Mar 11 09:54:56 2019 No.10456551 >>10456548 nope.... i give up, i shouldnt post drunk... the 2nd one is right >>10456544

>>	Anonymous Mon Mar 11 09:57:43 2019 No.10456559 File: 841 KB, 780x772, easy.png [View same] [iqdb] [saucenao] [google] >>10451483 Not hard at all

>>	Anonymous Mon Mar 11 10:02:17 2019 No.10456566 File: 149 KB, 500x348, medal.jpg [View same] [iqdb] [saucenao] [google] >>10451776 This.

Anonymous Mon Mar 11 10:19:43 2019 No.10456610

>>10456544
no it isnt...
https://www.wolframalpha.com/input/?i=sqrt(a%5E2+%2B+b%5E2)+%3D+10;+a*b+%3D+30;+p+%2B+q+%3D+10;+6+%3D+sqrt(p+*+q)
the altitude apparently divides the hypotenuse into sections p and q and h = sqrt(p * q).
and if you take that into account, the triangle would be impossible....

>>	Anonymous Mon Mar 11 10:25:59 2019 No.10456620 >>10450267 Well, Cheryl can go to hell if she thinks she's getting something from me.

>>	Anonymous Mon Mar 11 10:29:25 2019 No.10456623 >>10450270 But bookworms do start inside the volume. They are present in the wood slat used in the binding of the book.

Anonymous Mon Mar 11 11:55:01 2019 No.10456835

>>10454499
Yeah, but this isn't presented as a game theory problem. It's presented as "how would you do this in the real world" to kids. Any child who comes up with such a solution and thinks it would actually work in the real world has severe social problems.

>>	Anonymous Mon Mar 11 14:36:39 2019 No.10457258 >>10450178 7:05?

>>	Anonymous Mon Mar 11 14:43:05 2019 No.10457269 >>10450267 I did this once and it was easy.

>>	Anonymous Mon Mar 11 14:53:25 2019 No.10457286 File: 11 KB, 320x319, IMG-20190208-WA0004.jpg [View same] [iqdb] [saucenao] [google]

>>	Anonymous Mon Mar 11 15:01:36 2019 No.10457306 >>10450267 Sounds like May 19th, but someone who got an 84 on the TOEFL test made this so it's hard to say.

>>	Anonymous Mon Mar 11 15:04:05 2019 No.10457316 >>10452236 It's ridiculous to say that it should show anything. If that's the question, then all the watches should show the same thing.

>>	Anonymous Mon Mar 11 16:01:51 2019 No.10457488 >>10455505 White, because you're at the North Pole.

Anonymous Mon Mar 11 16:34:18 2019 No.10457592

>>10457286
[eqn]
\begin{cases}
\begin{alignat*}{3}
a &+ a &&+ a &&&= 30 \\
a &+ b &&+ b &&&= 20 \\
b &+ c &&+ c &&&= 9 \\
\end{alignat*}
\end{cases} \\
\therefore a = 10,\,b = 5,\,c = 2 \\
\int_{b+b-a}^{\infty} \frac{b\sin\left(x\right)}{cx}\,dx = \int_{5+5-10}^{\infty} \frac{10\sin{\left(x\right)}}{2x}\,dx = 5 \int_{0}^{\infty}\frac{\sin{\left(x\right)}}{x}\,dx \\
\textrm{Wolfram|Alpha tells me that this is equal to } \frac{5\pi}{2}.
[/eqn]

>>	Anonymous Tue Mar 12 06:17:58 2019 No.10459303 >>10450250 So, the answer is undefined. ***** = 5 (5 small petals) ++++ = ? (4 big petals) you are assuming that ? is 4, but that assumption does not have enough evidence

>>	Anonymous Tue Mar 12 06:21:05 2019 No.10459305 File: 512 KB, 480x270, autism.gif [View same] [iqdb] [saucenao] [google] >>10459303

>>	Anonymous Tue Mar 12 10:40:16 2019 No.10459695 >>10450214 81,assuming the value of blue corresponds to the number of petals, and the value of yellow corresponds to the number of flowers. This seems valid from the given information until disproven

>>	Anonymous Tue Mar 12 11:13:08 2019 No.10459744 >>10450267 This is grammatically confusing and the solutions posted only show that formal Logic is practically speaking in tongues and that Dialectic is the only truth.

>>	Anonymous Tue Mar 12 17:38:12 2019 No.10460636 >>10450261 I love you. Do you love me too?

>>	Anonymous Tue Mar 12 17:40:46 2019 No.10460646 >>10460636 Wait I meant to send this to the anon who made >>10457592. They are an intellectual.

>>	Anonymous Tue Mar 12 18:20:37 2019 No.10460758 >>10450178 Consciousness

Anonymous Tue Mar 12 18:33:24 2019 No.10460798

>>10460636
>>10460646
Thank you! Likewise; I can appreciate the genius of any [math]\LaTeX[/math] connoisseur.
I did fuck that one up a bit, though:
[eqn]
\int_{b+b-a}^{\infty} \frac{b\sin{\left(x\right)}}{cx}\,dx \textrm{ should have been } \int_{b+b-a}^{\infty} \frac{a\sin{\left(x\right)}}{cx}\,dx.
[/eqn]
I still got the right answer because I fucked up after that, though.
Let's hope that there's another question here where using [math]\LaTeX[/math] to solve it would be relevant eventually!

>>	Anonymous Tue Mar 12 19:07:55 2019 No.10460906 File: 14 KB, 819x141, AcroRd32_2019-03-12_16-07-31.png [View same] [iqdb] [saucenao] [google]

>>	Anonymous Tue Mar 12 22:59:26 2019 No.10461624 >>10450320 Holy fuck I haven't understood that question since i saw it ~4 years ago. THanks anon

>>	Anonymous Tue Mar 12 23:02:03 2019 No.10461639 >>10450312 stand back guys, some kike just discovered how to interpolate and is showing off some polynomials

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/sci/ - Science & Math