# Algebra help!!!

Ok, so I decided to go back to school after a looong layoff. Long enough that I have to take a placement test again. I picked up a packet of sample questions from the testing office and the english is no problem, but some of the math is giving me fits. (I used to be very good with math so this is really pissing me off)

Here’s the problem:
Sam and Mary each owned one-half stock in a printing company. Sam sold 2/3 of his stock to mary. What fractional part of the printing business does Mary now own?

I know that the answer is 7/10 because that’s what the answer key tells me… but WHY is the answer 7/10?

Sam sold 2/3 of 1/2 of the company stock to Mary. 2/3 * 1/2 = 1/3. So Mary now owns 1/2 + 1/3 of the company stock, or 5/6. Not 7/10–I’m not sure where they got that from.

I knew 7/10 sounded wrong. Damn it! of=x… 2/3 of 1/2 -> 2/3*1/2
:smack:
I should’ve remembered that… that’s one of the basics!

Thanks ultrafilter.

No problem.

Is it possible that you misread the question? If the question stated that “Sam sold 2/5 of his stock to Mary,” then 7/10 would indeed be the answer. Or it might be that the person who wrote the question intended to write 2/5, but put down 2/3 by mistake.

No, I copied it directly off of the page.

A key thing to word problems is remembering words. Pick up any algebra textbook and you can find a glossary of terms. Off the top of my head

of= multiply
is = equal to