Hi All,

Note-taking is a MUST on Test Day. Here, with so many numbers and variables to keep track of, missing one small detail could very easily cost you the question (and not taking enough notes is a silly reason to get a question wrong)..

Here, we're given 7 values for the number of books read by 7 students: 5, 10, 20, 29, P, Q and R.

**NOTE: I have arranged the numbers from least to greatest; the variables could be ANY number greater than or equal to 0)**

We're asked for the RANGE of values, which means that we'll need to know the LARGEST - SMALLEST numbers in this set of 7 values.

Fact 1: 5 < P < Q

Since we don't know anything about the values of P, Q and R, it would be easy to say this Fact is insufficient, but here's the PROOF:

IF....

P = 6

Q = 7

R = 8

Range = 29 - 5 = 24

P = 6

Q = 7

R = 100

Range = 100 - 5 = 95

Fact 1 is INSUFFICIENT

Fact 2: P < R < 15

Much like in Fact 1, we don't know the value of P, Q and R. Here's the PROOF that this is insufficient.

IF....

P = 6

R = 7

Q = 8

Range = 29 - 5 = 24

P = 6

R = 7

Q = 50

Range = 50 - 5 = 45

Fact 2 is INSUFFICIENT

Combined, we know...

5 < P < Q

P < R < 15

We can use the SAME TESTs that we used in Fact 2 (above) to prove that the answer is inconsistent.

Combined, INSUFFICIENT

Final Answer:

GMAT assassins aren't born, they're made,

Rich

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Official Guide 2016 Question Breakdown:

http://gmatclub.com/forum/empowergmat-blog-198415.html#p1527977

Rich Cohen

Rich.C@empowergmat.com

http://www.empowergmat.com

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