Bethany K. answered • 03/07/13

French in Real Life Tutor - Conversation, TPR, and More

Andrea, I understand why you're getting that answer and it's a simple mistake. Using PEMDAS is absolutely the right thing to do, but what you might not have realized is where you're getting confused.

So, let's review. PEMDAS:

P(arenthesis), E(xponents), M(ultiplication), D(ivision), A(ddition), S(ubtraction)

Now, let's take the equation that you are working on and go down the list.

12 - 1 x 0 + 4 / 2=

Are there any parenthesis? No.

Exponents? No.

Multiplication? Yes. So let's solve that first. 1 x 0 = 0 12 - 0 + 4 / 2 =

Division? Yes, let's do that next. 4 / 2 = 2 12 - 0 + 2 =

Addition? Yes. Now this is the part where you probably got tripped up, because there's that tricky little subtraction sign. I know what you're wanting to do is add

0 + 2 to equal 2, then solve 12 - 2.

However, 0 + 2 would have to be in parenthesis in order to solve it that way. It would look like this:

12 - (0+2) = instead of 12 - 0 + 2 =

So, because there is no parenthesis, the minus sign is only for the 0, not for the 0 and everything else afterward.

So instead of subtracting 12 - (2) = 10

you are solving each piece separately: 12 - 0 = 12 12 + 2 = 14

Voilà! The answer is, in fact 14.

It's easy with that part to get confused, because it seems like you're not following the order of operations (addition before subtraction). But in fact, you are still following the rules, because as we said before,

12 - 0 + 2 =

does not have a parenthesis sign. So really what it would look like through the PEMDAS goggles would be

12 - 0 + 2 = 12 - +2 = where the + would win because the - doesn't have a number attached to it anymore.

Therefore, 12 - 1 x 0 + 4 / 2 =

12 - 0 + 4 / 2 =

12 - 0 + 2 =

12 - + 2 =

12 + 2 =

14

Tada! :)