/sci/ - Science & Math

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bro what the fuck is this shit, this is triggering my autism

>>10412822
I dont understand

>>10412819
>le common core bogeyman xD
retarded teachers bottom of the barrel have always existed
just because you learned some mechanical calculation way of thinking about maths and refuse or are unable to understand why common core makes sense, does not mean it is nonsense
stop listening to /pol/tards

>>10412850
Most of these are probably fake anyway but common core remains stupid either way

>>10412852
It actually makes perfect sense.
It is a sort of formalization/standardization of the mental calculations people transform expressions to when they do it in their heads anyway
like splitting into hundreds/tens/ones and adding the partial sums afterwards
b00mers (in the literal meaning of the word) refuse to see that it is the same thing though because "back in my day..."

>>10412852
Education is pretty stupid in general. Why go to school when you can have sex?

>>10412858
>b00mers
also poltards because "muh sjw boogeyman indoctrinating our childrun xDD"
for all the time they spend talking about npcs monkeying stuff, they sure have some issues themselves.

>>10412860
t. aldous huxley
>>10412820
literally nothing wrong with any of this

>>10412832
Common Core.

Do Americans really just grab any old felt tip pen they have lying around to grade things? Do your teachers use crayons also? No wonder everyone considers your education a joke.

>>10412822
You go to the closest whole number with 0s on the end for efficiency. You’re supposed to do this because it saves time. 103 equates to 100 (roughly) and 28 equates to 30(a little more smoothly).

Overall the equation is 100- 30. It’s 70. What don’t you understand?

>>10412889
Dumb european

>>10412889
How about your shitty country make as much money as we do then talk shit faggot

>>10412819
Marty's pizza is at least 5/4 times bigger than Luis' pizza.

>>10412832
actual problems from math curriculum in the USA

>>10412864
>literally nothing wrong with any of this
'Fixing' things that don't need to be fixed.'Fixing' things by making them unnecessarily complicated/dumb.

>>10412891
not anon
it makes sense but is a bit unfortunate since working in 25's is almost as easy as in 10's.
And the one who graded it said it was plain wrong, instead of suggesting the alternative of going to 100-30

>>10412891
I T
I N S T I L L S
I D I O C Y

continuing...

>>10412907
>'Fixing' things that don't need to be fixed.
>teaching one thing and then having people do a separate think in their heads (that they either learn or do not learn on their own)
is hardly better than
>teaching the thing people do in their heads
in the first place

>>10412907
>'Fixing' things that don't need to be fixed.'Fixing' things by making them unnecessarily complicated/dumb.
for u

3.

>>10412913
how about posting the entire explanation instead of cropping out half of the reason for why it makes sense?

>>10412917
yeah you are clearly just trolling, this has nothing to do with common core.

>>10412913
So how do YOU add 34+18 in your head anon if not by
[math]34 \rightarrow 44 \rightarrow 50 -> 52 [/math]
or if you have enough practice to:
[math]34 \rightarrow 44 \rightarrow 52 [/math]

or doing the ones first:
[math]34 \rightarrow 40 \rightarrow 42 \rightarrow 52[/math]
or (again skipping the breaking up of the ones to reach a 10)
[math]34 \rightarrow 42 \rightarrow 52[/math]

in before "I just do it/memorized it xD"

if you are just going to shitpost images in bad faith then there is very little to discuss.

>>10412913
>common core 5
>>10412917
>common core 57
Is this just your autistic obsession? Do you even like math?

>>10412909
She did suggest it. It IS wrong. Instead of working in rounded 0s he used numbers between the tens.

>>10412910
How?

>>10412819
This is incredible. The answer is MORE abstract than the common core set answer. This child is a prodigy.

>>10412820
Right is pretty much what I do in my head when trying to calculate things, but on paper I do left.
I wasn't taught Common Core, it's just more sensible to break it down like that to minimize errors, but when you have paper it's much faster to do left.

>>10412917
It obviously takes five minutes to saw lengthwise.

You’re just going by width. That’s the first sawing

>>10412819
why crop out the part that states all pizzas are of equal size?

>>10412933
Yes, but 5s are almost as good as 10s, so the example is a bit unfortunate.
If the sum was something inbetween 70 and 80 not including 75 then the working with 10s would have been a bit more justified, right?

I just hope the grader gave a verbal comment along with the written one clarifying this, because somebody who has figured out that two 5s make a 10 and use that in their head might be demotivated.

>>10412913
Knowing that 6 +7 = 13 (would be fairly instant result in most childrens' heads by that stage) I would rather just take 7 from the 17 and add it to the 26, making 33 and then add the 10.

Going through this weird process of deducting enough from 17 to take 26 to 30 and then adding the rest is pretty dumb.

>>10412858
In my opinion for the stuff you do in middle or high school you don't need an elaborate sytem to explain the mental steps in order to do basic arithmetic operations. For the less fortunate kids it may be helpful but I believe that plain practice helps you a lot more. Everyone does it differently but being able to do basic calculations quickly in your head is something you have to work for

>>10412891
Or you just add the ones til you get 5 and then the tens till you get 70. It's much more useful and just as easy. It's just substation

>>10412913
I see where they were going with this but try explaining that to a kid

>>10412822
If the broader section of the quiz was estimation then the teacher is right, but the question itself says nothing about estimation.

>>10412917
I legitimately don't understand, is this just a dumb teacher?

>>10413031
>is this just a dumb teacher?
Yes.
Probably thinking "cut two pieces from a board" rather than "cut a board into two pieces" which takes just one cut, and into three pieces takes two.

>>10412944
So we have to change the method if it’s ending in five? You’re making things way too complicated man, even I don’t do this kind of stuff

Reminder that all the techniques you think of as "normal math" were widely derided as incomprehensible in 60s when they were introduced as "New Math".

Is America ahead when it comes to math in the world?

>>10413073
America is only really ahead in a couple of places:
institutional knowledge of engineering disciplines
institutional knowledge of business disciplines

>>10413074
But IT?

>>10413075
yeah that's what I said

>>10413036
>So we have to change the method if it’s ending in five?
no, but telling kids who have found it works for 5 that they are wrong without further explanation is unfortunate

>>10412864
Part of it is literally newspeak you dumb brainlet.

>>10413077
>no, but telling kids who have found it works for 5 that they are wrong without further explanation is unfortunate
ㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋ

>>10413022
>If the broader section of the quiz was estimation then the teacher is right
Yeah, obviously, so why are we even talking about this?
The answer is that most retards don't even consider a greater context to these shitposts

>>10413067
this

>>10412913
This isn't cringy you absolute retard.

>>10412938

>>10412913
makes sense to me, that's how i do it.

>t. phd student

>>10413147
teaching estimation instead of accuracy IS the problem

>>10413214
?

>>10413213
Why not:
20+10=30
6+7=13
13+30=43

>>10413067
>Reminder that all the techniques you think of as "normal math"
How about a few selected bits from new math survived? Kids are no longer drilled in transformation between bases or set theory operations.

>>10412917
Your decade-old shitpost is from the Math Super Stars program that some Florida schools use as an extracurricular activity. Most of the time VOLUNTEERS are used to score the papers and they may or may not have the answer sheet that goes with it.

You do realize it's a foreign interest scheme to rob the next generations of intelligence right.

This is your last warning. Wake the fuck up.

>>10412819
I knew burgers were retarded but holy shit

>>10412858
>It is a sort of formalization/standardization of the mental calculations people transform expressions to when they do it in their heads anyway
that’s retarded

>>10412819
to be fair, in grade school math the teacher said you can't subtract a bigger number from a smaller number. So I raised my hand and said negative numbers exist. The teacher told me I was right but she was trying to keep the lesson simple to make a point about the math she was teaching at the time.

So it's not like common core is the start of this.

>>10413422
Ok there are two things that are wrong with this.
1) if you actually wrote the right answer on a test you shouldn't be penalized for knowing more.
2) in the case of positive and negative numbers the teacher did have a point.
If your limit your answers to positive numbers then a negative answer is not a solution.
This is correct, useful and applicable in real life situation.
But saying stuff like 103-28 = 70 is just plain wrong and stupid.

>>10412822
It is trying to get the child to use rounding. Round up for 28 and down for 103. That has nothing to do with, "estimation," or, "common core." It is using incorrect terminology.

itt: burgers actually defending this shit

>>10412907
But it does need to be fixed anon. the way we teach math is dumb.
Common core is an attempt to teach people how to actually reason their way to the answer rather than perform number art on the paper to magically generate the correct answer.
When you teach these "simplified" "commonsense" strategies you never know what bizarre patterns or techniques people actually internalize
The shit you currently see on the undergrad level as an instructor is just incredible

>>10413415
Make your case why that isn't a better way.

>>10412864
>literally nothing wrong with any of this
The font

>>10413703
>shit you see on the undergrad level

Expand on this please

>>10412936
He is not. Common core is holding back children.

>>10412891
They should use larger numbers and not be picky about the resolution of the estimate. There are plenty of people who can quickly subtract a two digit number from a three digit number in their head.

>>10412822
>>10412917
honestly, fuck teachers. common core, whatever, these people are supposed to at least be able to do elementary school math, and marking a correct answer as incorrect is them failing at their job and hurting the minds of children

>>10413826
Some execute procedures as if reading tea leaves or tarot cards.
e.g. in a junior-level EE course, on a question regarding sensor input. 12 students out of ~50 decided that [math]y = f(x) \implies x = \frac{y}{f}[/math], then stopped there, unable to go any further and unsure of what went wrong.

Some don't understand arithmetic so they if they make a mistake in the procedure they can't identify it. Student (in an EMF course) multiplied two fractional numbers (i.e. between 0 and 1) together with calculator, came up with result larger than either of the two numbers. Proceeds to blindly carry this obviously invalid result forward into the problem, gets stuck, wonders if perhaps the question is broken.

Sometimes you teach a technique and they distill it into a pattern which is overly simple and incorrect, or form a mental picture of the system which is wildly incorrect (particularly in programming courses). But they don't (or can't?) know their mental picture is wrong and will swear up and down that they understand the material, so it's hard to get them to examine it.

And these aren't the remedial bunch. These are electrical engineering majors at a tier 1 university.

>>10412942
not my pic, came that way

>>10413216
why spend time on shooting arrows out into the target range when the kids are capable of hitting the target?

>>10413329
makes it even worse:
been going on for a decade, and even if it isn't still going on the people who were taught from it are out in society...maybe counting votes in Broward County?
Also, why in fuck are there VOLUNTEERS? isn't that a violation of teacher's union shit?
also, have things gotten better in the last decade??

>>10413422
>The teacher told me I was right but she was trying to keep the lesson simple to make a point about the math she was teaching at the time.
I see her point, but I also see how keeping it simple now creates problems the kids will have to overcome in the future. Bad teaching, really.

>>10414120
With the remedial team it's even worse. A professor i know well (from a different university) talks about students in "college algebra" knowing how to "FOIL" to expand factors into polynomials, but sitting like a deer in headlights if they encounter anything more complicated (say, if one of the factors has 3 terms instead of 2).
After all, just FOILing the ones they could FOIL and ignoring the rest would get at least a C on a math test and get them through. They get a diploma from high school. And then it falls to him to try to teach properly in only 1 semester what they were supposed to be learning for the last 7-8 years. And that's pretty hard when some of them never even understood multiplication in the first place.

>>10413462
>But saying stuff like 103-28 = 70 is just plain wrong and stupid.
But they didn't say that.
The question asked: is the answer of 75 reasonable? That's a yes or no question.

>>10414152
i feel like more personalized time with a student would help overcome this. they shouldn't hold a kid back from studying math or whatever subject deeper and having a greater understanding just because other students are too slow, but they also shouldn't make the slow kids get super confused and fuck their education.

>>10412919
not my pic, got it that way

>>10412822
This bugs me. I only like to mark someone down for not having enough information, not for doing too much. Leaving a note explaining what you were looking for is fine, but dinging a point? Nah.

>>10412860
t. nigger

>>10412820
This is actually pretty based. Good job teacher.

>>10414120
>junior level EE
>can't do basic algebra
I'm going to have to call bullshit, you need to take up to calc II, sometimes even diffeq in order to be admitted to a college of engineering
There's no way you pass such advanced classes and make mistakes like that

>>10412917

>>10412930
Not him, but if it were me, I'd mentally do: 30 + 20 = 54, then minus 2, so the answer is... 52!

>>10412819
Holy shit. So this is why so many people turn out retarded. How do we end up with teachers like this? They were outsmarted by a first grader.

>>10415423
Because teaching degrees are trash and require submitting to the system rather than independent thought or talent or charisma

>>10415161
>I'm going to have to call bullshit, you need to take up to calc II, sometimes even diffeq in order to be admitted to a college of engineering
But that's exactly the point anon.
This type of student got C's or maybe B's in calc 2, multivariate and diff eq by """solving""" problems presented in the exact format of example questions, homework questions, etc.
As soon as it's presented in a different format or we raise the level of abstraction, they completely forget their "knowledge" of basic algebra.
(I was simplifying when I said y=f(x) so you would understand the mistake they made, in reality the f was the greatest integer function and x was an expression of its own)

>>10412907
t. Retard

This is a good way to teach math. First of all it provides a more intuitive and deep learning tool for understanding how to break addition of larger numbers down into smaller steps that are more digestable. This is precisely the process that allows us to perform a sum like 237993463 + 37195629, which I imagine you would have more difficulty solving without dissecting into smaller steps.

Furthermore, it provides students with a better understanding of the nature of the inegers and the operation of addition.

>>10415328
no cuz 2=10 and 4=20 so 3=fIfTeEn

>>10413329
thanks for digging that up

God my American public education was the bane of my existence. Literally every class was a fake mandatory attendance class. I dropped out in middle school and am not the top of my class in college.

I literally took Algebra 1 4 years in a row in middle school and high-school. It only took a couple terms to catch up to calculus in college.

>>10415642
*now the top of my class
god im so fucking tired fucking fucking so much work to do. I couldn't even do 30 min of homework in highschool but i do 6 hours a day now

>>10415646
good for you, m8

>>10413376
https://gizmodo.com/whats-bigger-1-3-pound-burgers-or-1-4-pound-burgers-1611118517

>>10412820
The "new" way to solve addition is just the way people do it in their head. I don't think it is bad to teach this but they should teach the traditional algorithm also and get rid of the newspeak.

>>10412822
I fucking remember this "estimation" bullshit in school and I'm 27
They literally marked me wrong because I got the correct answer
and I quote: "estimations are supposed to be wrong, if you got the right answer, you didn't estimate correctly"

>>10412822
If you were to estimate that, 100-30 is inconsistent rounding because 3 is closer to 5 than to 0 so 103 rounds to 105.

>>10413067
what was old math then?
How would i add 57 and 39 in old math?

>>10415731
I dont believe this, americans are far more comfortable with fractions than metric users since many of our units of measure are fractional.

>>10415423
Protip: it was a parent trying to frame le gommon gore D: boogeyman.

>>10412819
>4/6

>>10413022

It asks if it's a reasonable answer, which implies estimation. The only shortcoming of the question for me is that it included the actual answer in the question as opposed to a nearby figure. These sort of fundamentals are the foundation of concepts like Fermi estimation, which provides ballpark calculations for subjects that would prove too time consuming for data collection alone in order to produce an exact figure.

>>10412819
Aren't teachers supposed to have the answers available to them when marking school work?

>>10412917
Who the fuck takes 10 minutes to saw a board in half

>>10412852
this 1 >>10412822 isnt fake. I remember doing it in early grade school. Completely forgot too until I saw this image

>>10412858
>It is a sort of formalization/standardization of the mental calculations people transform expressions to when they do it in their heads anyway
It isn't. This sort of thing is the newest result of the American obsession with maths being a bunch of prescribed algorithms. In Europe we're taught a few techniques and a number of different ways to break down a problem.

>>10412819
What a shitty question.

>>10413225
For me its
20-3=17
26+20=46
46-3=43

>>10416150
We need an explicit formula Tyrone can memorize to plug and chug for the answers so no child is left behind.

>>10413864
>There are plenty of people who can quickly subtract a two digit number from a three digit number in their head.
you say that as if it's something special.i hope you meant everybody. if you can't even do that you should probably not reproduce

>>10413213
brainlet

>>10415993
women

>>10412930
40 + 12

>>10413216
if you want to juggle as a clown you have learn to do it right in order to be able to fail in a funny way. math is the same. teach the children first that a correct answer exists and that accuracy is desireable, then introduce harder problems involving rounding up and down which will involve correctly working with the rounded numbers anyway.

Why do people act like there weren't incompetent elementary school teachers before Common Core?
A lot of "lol common core" pictures people post aren't even -bad-, and some of them predate Common Core in the first place. The poster just doesn't understand them.

Reminder that public school curriculums in America are set by the 1% to keep the children of the masses from being able to compete for university admissions and careers with their own kids who go to private schools from the time they can walk.

>>10412930
This >>10417493

>>10413703
Loss?

>>10412820
math situation is pretty hilarious
what's wrong with problem?

>>10412917
that's because she got xp in the first time, so she needs only half of time in the second.

>>10419620
Problem is a negative word. Can't have our little chillins facing any sort of negativity, can we?

⤶ ⤶ ⤶...AND I'M BACK. Howdya like this one?

>>10417518
w what?

>>10415328
did you really spend time making this animation? I adore you anon

>>10412858
if thats how you do math in your head you are pretty stupid yourself mate

>American Education

>>10412819
So the question blatantly lies to you then you're supposed to say that it's lying? That is tricky and not math.

>>10412819
Common core isn't retarded per se. It actually makes a lot of sense, and if you haven't already memorized a certain solution, then it's what you would have done in your head. If you didn't know what 6 + 7 was from memorization, it makes sense to add 6 + 4 + 3, that's just an easy way of breaking down a math problem.

The problem is that schools come up with these retarded lesson plans that make no sense. It's not every school, but all the images you see online are from retarded lesson plans and aren't reflective of common core. They likely would have been just as retarded if you go back 20 years.

>>10421943
I mean the teacher is just retarded, nothing new here.

>>10412819
Why are they even being marked with texters?

>>10412820
None of this is "wrong", just unnecessary.
In highschool I had this burned out calculus teacher who told me public education will always be changing because as long as they can get the school board to admit there's a problem with the way they currently teach, the they can get more funding. And the board will always admit there's a problem when a feasible solution to said problem already exists ("common core" AKA the way shit has always been taught with a new skin).

>>10412930
34+18 = 34+20-2

>>10421943
5x3 is not the same as 3x5
4x6 is not the same as 6x4
This teacher is prepping them for learning matrices in the future.

>>10414156
>>10413826
I tutored one semester in undergrad. At my large well ranked state school everyone in the business college was required to take pre-calculus, and anyone in the math department could get paid to tutor these guys because there was so many of them that desperately needed help.

It was unreal the kind of people I saw, it made me sick that I might share a diploma with some of them. You've probably met people that say "oh I'm bad at math". The reason is because they don't try to learn it, they come up with excuses such as "I was never taught that". Right I'm sure your teacher never taught you the area of a circle formula but decided it would be a good quiz question lol

>>10421943
This is a great example of why active measures and subversion have become so successful in the states. Someone takes something created intentionally wrong/seditious, then for some reason people continually keep arguing against it and spend thier own time doing so as if it's still valid.

You can push the most stupid shit in any given culture as long as you can tap into peoples need for constant self vindication.

>>10412858
You're making the assumption that the way people initially learn to do math in base ten is the way that they are stuck doing these calculations for the rest of their lives. If anything that is pretty much the worst possible outcome because doing math like this is significantly slower than doing it by the older methods and at the same time there are far faster and more efficient methods to do math.

The principals behind common core are fine if your intent is to use them to help students who are struggling with basic math comprehension gain comprehension, however that's not what's happening. What's happening is that EVERY student is being forced to use this system, when most of them don't need to bother with this stuff and in fact it's just going to slow them down and make them hate math because of how fucking over-complicated it makes everything.

What should be done is that students should be taught in the traditional manner until it's clear that they either are building comprehension or they aren't, if they are then they should continue with the traditional methods, supplemented with advanced mathematics techniques that would make things quicker and more efficient for them in the future. Meanwhile, all of the students who aren't building proper comprehension should be placed in remedial classes that teach a system that is similar to common core but is specifically meant to catch them up to their classmates and then immediately be pulled out of those classes once they build the comprehension they were lacking.

But no, we can't have a system like that, because that would require too much attention from the teachers who would much rather just be given a curriculum to teach to every student regardless of whether or not they are struggling with it or excelling beyond it, then turn around and complain about how bad the curriculum is.

>tfw I had actually had a math teacher who did this exact dumb shit when I was in school before common core

>>10423936
What you just did is common core math

>>10412930
I'll spit some numbers at you and work through them as they go in my head for science

>17+435
7+5=12
452
>632+880
600+800=1400
1512
>101+907
1008
>605+313
918
>635+499
9+5=14
504+630=1134
>191+286
90+80=170
101+170+206=477
>567+257
824
>76+153
70+50=120
229
>643+225
868
>802+231
1033

I kind of just try to autocomplete simple shit in my head as much as possible without having to think about it at all. Like if there's a ten's place that doesn't have anything to do with anything else I try my best to just kind of let my brain do it's thing while I focus on the other shit with the hopes I'll just kind of have computed it by the time I come back to it. Just because actually setting the math up in my head takes more time to do than actually doing the math.

That said, my arithmetic is shit. I need to practice it more. It's convenient as shit.

>>10413703
That picture made me roll on the floor laughing

>>10413329
based

>>10423944
I doubt the teacher who marked that sheet knows what a matrix is

>>10423958
go on...

>>10423967
>common core math
is demanding the non-gimps to use crutches, and penalizing them if they do math in a non-retard way

>>10413213
>>10417476

I do this as well.