So my mom failed the math part of the THEA on her first attempt, but she's trying to study, and as I was trying to help her we came across. . . 4(-2) ÷ (-4)(2) She says 1. I say 1. The book says "Don't be tempted to say 1. The answer is actually 4." I see how they GET 4, but even using the order of operations, I don't see how the right answer can possibly BE 4. Multiplication before division, right? I guess the parentheses make the answer different, but howso? It'd be nice if someone could explain this to me.
http://www.mathgoodies.com/lessons/vol7/order_operations.html This says work from left to right. So: -8 / (-4)(2) 2(2) 4
I have no idea why but 4 is correct http://www.google.com/intl/en/help/features.html#calculator http://www.google.com/search?q=4(-2)+/+(-4)(2)&btnG=Google+Search
Multiplication doesn't come before division. They're both the same thing...as in (4 / 2) = 4 x 1/2. Seeing as how none of the parentheses surround any particular operation, none of them take priority over another. Therefore, you simply work from left to right sequentially. 4 x -2 / -4 x 2 = 4
multiplication and division are both equal in order, yes, it is very easy to say 1, but when you work left to right with order of operations it is 4
Thanks guys. I can't say I'd ever get that question right on a test, but I see how 4 is the right answer. Thanks.
The reason you think it is one is because you are reading it like this: (4)(-2) ------- (2)(-4) But since there are no parentheses, the equation reads like this: (4)*(-2)/(-4)*(2) It doesn't matter whether you work left to right, middle-out, or right-to-left. You are reading it wrong.
The wat to remeber it is Please (parentheses) Excuse (exponents) My (multiplication) Dear (division) Aunt (addition) Sally (subtraction) or PEMDAS
Where is the calculus with analytical geometry ? I want your mom solving problems using Stoke's Theorem, NOW!
