/sci/ - Science & Math

I'm having trouble with an algebra problem. This is it.


12 ( ( 5/6 + 3/4) - 1/6)
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5 √ 2 (3)^2 + 7

My answer comes out to = 12(8+9) / 25

The book claims the answer is 17/25, though.

I have no idea what they did with the number 12. Can someone clarify this?