Answers to Practice GRE Test Quant Questions

Post: Did You Know these Facts about GRE Math?

Question: How many positive integers, less than 20, are either an even multiple of 2 or, a multiple of 9 or, the sum of a positive multiple of 2 and a positive multiple of 9?

Answer: There are 11 such integers:

  • Multiples of 2–4, 8, 12, 16 (total 4)
  • Multiples of 9–9, 18 (total 2)
  • Sums of a positive multiple of 2 and a positive multiple of 9–11, 13, 15, 17, 19 (total 5)

Post: Quantitative Comparison Questions: Doubtful D!

Question:

X < (1/X)

Column A Column B

X X2

Answer:: (D)

The given inequality is X< (1/X).

This is possible only in two cases:

(1) If 0 < X < 1 OR

(2) X < -2

Now, you need to compare ‘X’ with ‘X2’

If you pick the value of ‘X’ from 1st range, let’s say ‘X’ = ½, then X > X2, thus the possible answer is option (A) and hence, options (B) and © can be eliminated.

But if you pick up the value of ‘X’ from the second range of values, lets say X = -3, then X < X2.

That means we are not able to reach to any unique conclusion using the information given, thus the answer is option (D)

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