Source: Revised GRE PDF 2nd Ed. Section 6; #5 (p. 86)

13

T is a list of 100 different numbers

T is a list of 100 different numbers that are greater than 0 and less than 50. The number x is greater than 60 percent of the numbers in T, and the number y is greater than 40 percent of the numbers in T. Quantity A: x - y Quantity B: 20 Quantity A is greater., Quantity B is greater., The two quantities are equal., The relationship cannot be determined from the information given.

2 Explanations

5

Erica Baker

AD CG,

I didn't understand it at first either, but let me try to help break it down:
If there are qty 40 number 1's (could include decimals if you want to be technical about "different numbers" which is not the same as "different integers") in the list T of 100 different numbers and y=2, then y is greater than 40% of the numbers.

Now there are also going to be qty 20 number 2's. So now we have qty 60 numbers in our list of 100 and x=3 which makes it "greater than 60 percent of the numbers in [list] T."

Then, x - y or 3 - 2 = 1 which is less than quantity B, BUT x could also be any number up to 49 so x - y would then be 49 - 1 = 48 which is more than quantity B.....so we have to select choice D.

Nov 12, 2014 • Comment

7

Gravatar Chris Lele, Magoosh Tutor

Sep 27, 2012 • Comment

AD CG

I still don't understand this explanation.

Nov 2, 2014 • Reply

Francisco Olivas

Does it mean that I could pick any two numbers to reach D? Would the following numbers be okay: x=2, y=1 then 2-1=1 then AB, then we pick answer D. Is my rationale okay? Thanks.

Oct 11, 2017 • Reply

Jonathan , Magoosh Tutor

Hi Francisco,
Yes, that's one possibility.
20% * 100 = 20 numbers must be between X and Y. The question doesn't specify the numbers must be integers, so we could have decimals, and we could have 20 numbers between 1 and 2. 1.01 1.02 ...etc in this case B is greater.
We could also have x = 40 and y = 10 ...in this case A is greater.
X and Y could be ANY number between 0 and 50, as long as X > Y.

Nov 6, 2017 • Reply

Ramlah Merchant

What really tripped me up here was that I thought different meant distinct. Is it safe to assume that different does not mean distinct?

Nov 6, 2017 • Reply

Jonathan , Magoosh Tutor

Different DOES mean distinct. We have 100 numbers in T and they must all be different, all distinct and between 0 and 50. But there is no requirement that the numbers are integers, so we could have any numbers between 0 and 50 ...for example. 2.222 and 2.2221 and 2.22222 and 2.224 are distinct numbers.

Nov 13, 2017 • Reply

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