Integer

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Integer

by vinay1983 » Wed Oct 02, 2013 7:08 am
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by Brent@GMATPrepNow » Wed Oct 02, 2013 7:41 am
For the integers m,n,r, and s, if m + n = 250 and m > n, is (m - r) > (s - n)?
1) 250 > r + s
2) m + r + s = 375
Target question: Is (m - r) > (s - n)?

This is a great candidate for rephrasing the target question. We have a free video on this: https://www.gmatprepnow.com/module/gmat- ... cy?id=1100

If we take the inequality in the target question and add r and n to both sides, we get . . .
REPHRASED target question: Is (m + n) > (s + r)?

Since m + n = 250, we can also rephrase it this way . . .
REPHRASED target question: Is 250 > (s + r)?

Given Information: m + n = 250 and m > n
If m and n were EQUAL, then m and n would both equal 125
Since m is GREATER THAN n, we can conclude that m > 125

Statement 1: 250 > r + s
Perfect!
One of our REPHRASED target questions is Is 250 > (s + r)?
Since statement 1 allows us to answer the REPHRASED target question with certainty, it is SUFFICIENT

Statement 2: m + r + s = 375
Earlier (in the Given Information part of the solution), we determined that m > 125
So, we can reword statement 2 as: (a number bigger than 125) + (r + s) = 375
This means that (r + s) must be LESS THAN 250
In other words, 250 > (s + r)
One of our REPHRASED target questions is Is 250 > (s + r)?
Since statement 2 allows us to answer the REPHRASED target question with certainty, it is SUFFICIENT

Answer = D

Cheers,
Brent
Brent Hanneson - Creator of GMATPrepNow.com
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by mevicks » Wed Oct 02, 2013 7:44 am
For the integers m, n, r, and s, if m + n = 250 and m > n, is (m - r) > (s - n)?
(1) 250 > r + s
(2) m + r + s = 375
Simplify:
Is (m - r) > (s - n)?

IS (m + n) > (s + r)?
OR
IS 250 > (r + s) ?

Solve:
St1: Directly gives the relationship, 250 > (r + s), SUFFICIENT
St2: Its given that m > n and their sum is 250. So m has to be atleast 126. Thus m > 125
m + r + s = 375
r + s = 375 - 126 = 249
Thus 250 > (r + s)
SUFFICIENT
[spoiler]Answer : D[/spoiler]

Regards,
Vivek