Help w/ GMAT Prep DS Question

Problem Solving — algebra and arithmetic (GMAT Focus Edition)
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Help w/ GMAT Prep DS Question

by agkrause » Wed Jul 28, 2010 9:29 am
Hi - I was wondering if anyone knew a good way to approach the following problem:

Jason's salary and Karen's salary were each P percent greater in 1998 than 1995. What is the value of P?

(1) In 1995 Karen's salary was $2,000 greater than Jason's.
(2) In 1998, Karen's salary was $2,440 greater than Jason's.

I wanted to see if anyone had a more efficient way to approach the problem.

Thanks for taking a look,
agk
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by Tani » Wed Jul 28, 2010 12:15 pm
Try this:

Jason's salary = J
Karen's salary = J + 2000

after p% increase,

Jason's = (1+p)*J
Karen's = (1+p)*(J+2000)

The difference between these is $2,440.

Gives p = 22%
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by paruloberai » Sat Aug 07, 2010 2:08 am
agkrause wrote:Hi - I was wondering if anyone knew a good way to approach the following problem:

Jason's salary and Karen's salary were each P percent greater in 1998 than 1995. What is the value of P?

(1) In 1995 Karen's salary was $2,000 greater than Jason's.
(2) In 1998, Karen's salary was $2,440 greater than Jason's.

I wanted to see if anyone had a more efficient way to approach the problem.

Thanks for taking a look,
agk
Hi,

You could translate this problem into the following terms:
k = Karen's 1995 salary
j = Jason's 1995 salary
p = already defined in the problem

Then we have

(1) k = j + 2000
(2) k(1 + p/100) = j(1 + p/100) + 2440

None of the statements alone can give the value of p.

together: substitute j + 2000 for the first 'k'
(j + 2000)(1 + p/100) = j(1 + p/100) + 2440
2000(1 + p/100) = 2440
...so you can calculate p.
Hence, C.
Parul Oberai is a content expert for GMATLounge. She has a lot of experience helping GMAT students to be more efficient in solving quantitative problems. She can be reached at https://gmatlounge.com/ .