1 pages in 5/x min
P pages in 5p/x
A.
GmatKiss wrote:Derek can read X pages in 5 minutes. At this rate, how long will it take him to read P pages?
5P/X
5X/P
P/5X
5/PX
PX/5
How long?
This topic has expert replies
Source: Beat The GMAT — Problem Solving |
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maihuna
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X pages in 5 min
1 pages in 5/x min
P pages in 5p/x
A.
1 pages in 5/x min
P pages in 5p/x
A.
Charged up again to beat the beast 
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gmatboost
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Another approach is a proportion:
x pages/5 mins = p pages/z mins
cross-multiply: xz = 5p
z = 5p/x
x pages/5 mins = p pages/z mins
cross-multiply: xz = 5p
z = 5p/x
Greg Michnikov, Founder of GMAT Boost
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GMAT Boost offers 250+ challenging GMAT Math practice questions, each with a thorough video explanation, and 100+ GMAT Math video tips, each 90 seconds or less.
It's a total of 20+ hours of expert instruction for an introductory price of just $10.
View sample questions and tips without signing up, or sign up now for full access.
Also, check out the most useful GMAT Math blog on the internet here.
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tpr-becky
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Another way if formulas prove difficult or confusing - plug in numbers:
if x = 10 and p = 40 then if he reads 10 pages in 5 minutes how long to read 40 pages? 20 minutes.
Then plug the above numbers into the answers
A) 5(40)/10 = 20 (correct)
B) 5(10)/40 - too small
C) 40/5(10) - too small
D) 5/40(10) - way too small
E) 40(10)/5 - too big.
if x = 10 and p = 40 then if he reads 10 pages in 5 minutes how long to read 40 pages? 20 minutes.
Then plug the above numbers into the answers
A) 5(40)/10 = 20 (correct)
B) 5(10)/40 - too small
C) 40/5(10) - too small
D) 5/40(10) - way too small
E) 40(10)/5 - too big.
Becky
Master GMAT Instructor
The Princeton Review
Irvine, CA
Master GMAT Instructor
The Princeton Review
Irvine, CA
