Explanation

Say that x = 2. That means that over 60 percent of the numbers are less than 2. If you consider there are an infinite number of numbers between 0 and 2 when you use decimals. So the 60 percent would look like (0.1, 0.12, 0.1579, 0.2, 0.29,etc).

Say that y = 1. That would mean 40% of the numbers are between 0 and 1, and another 20% are between 1 and 2 to satisfy both y = 1 and x = 2. So x – y = 2 – 1 = 1. In this case, Quantity B is greater.

But what if x were at the other extreme of the range, such as x = 48? If we keep y = 1, that would mean that 40% of the numbers were between 0 and 1 and the next 20% were between 1 and 48 (and the remaining 40% were between 48 and 50). Now x – y = 48 – 1 = 47. In this case, Quantity A is greater. Thus, the relationship cannot be determined.
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One can even consider x and y to be only INTEGER value and still solve it.Given list of 100 numbers, x is greater than 60% of the numbers
60% of 100 = 60 numbers. So x is greater than 60 numbers. Means x ranges from 61 - 100
y is greater than 40% of the numbers
40% 0f 100 = 40 numbers. So y is greater than 40 numbers. Means y ranges from 41 - 100
Since there is an overlap among these two values, we cannot predict whether x-y is going to be greater than or less than 20.
If x=67 and y=97, then B>A OR
If x=97 and y=67, then A>B
SO answer is D

GIVEN: T is a list of 100 different numbers

GIVEN: x is greater than 60 percent of the numbers in T
So, if we were to list all 100 numbers in ASCENDING order, x would be the 61st value in the list (so that 60 of the 100 numbers are less than x)

GIVEN: y is greater than 40 percent of the numbers in T
So, if we were to list all 100 numbers in ASCENDING order, y would be the 41st value in the list (so that 40 of the 100 numbers are less than y)

We want to compare x - y with 20

Consider these two possible cases:

case i: The numbers, when listed in ASCENDING ORDER are:
0.1, 0.2, 0.3, 0.4, . . . . 4.0, y = 4.1, 4.2, 4.3, . . . . 5.9, 6.0, x = 6.1, 6.2, . . .
In this case, we get:
QUANTITY A: x - y = 6.1 - 4.1 = 2
QUANTITY B: 20
In this case, Quantity B is greater


case ii: The numbers, when listed in ASCENDING ORDER are:
0.1, 0.2, 0.3, 0.4, . . . . 4.0, y = 4.1, 4.2, 4.3, . . . . 5.9, 6.0, x = 40, 40.1, 40.2, 40.3 . . .
In this case, we get:
QUANTITY A: x - y = 40 - 4.1 = 35.9
QUANTITY B: 20
In this case, Quantity A is greater

Answer: D

Cheers,
Brent
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T is a list of 100 different numbers that are greater than 0 and less than 50. The number x is greater than 60% of the numbers in [i]T, and the number y is greater than 40% of the numbers in T.[/i]

..I couldn't access my last account anymore...so If I ask same doubts twice,...plz don't be angry,.. because I already lost my previous account,so I don't know where I was weak at to focus for.


anyway now my doubt in this question is...

can I take X value anything between 61 to 100 ..and y value anything between 41 to 100... ..
at some cases I got 20 as results if I take 61 as X and 41 as y.. can I take 99 as X and 99 as Y... result will be zero...

is it also a correct way of solving??..plz tell me

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Hi baraijaya

Let me try to help!

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.

The above highlighted portion says it all. As we are asked to select number greater than 0 and less than 50, it could be any number. Note we are asked it could be any number which includes decimals. Thus, sticking to the information given we can take up greater than 0 and less than 50. Note even in this case you can get x-y=20
Considering x=40 and y=20. But the twist comes when you can consider any number and get any value for x-y greater than or less than 20.

Thus the correct answer is D

Let me know if I can help further

Regards

Hey,

Let me check for your account.
And no-one would be angry. We are here to help. Feel free to post doubts.

Regards,
R