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Emdad
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If x/y = 3/7, then which of the following cannot be a possible value 05 May 2021, 02:12
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E
Be sure to select an answer first to save it in the Error Log before revealing the correct answer (OA)!

Difficulty:

95% (hard)

Question Stats:

20% (01:26) correct 80% (01:22) wrong based on 179 sessions

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If x/y = 3/7, then which of the following cannot be a possible value of (y - x)?

(A) 4
(B) 21
(C) 24
(D) 84
(E) None of these
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E
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Bunuel
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If x/y = 3/7, then which of the following cannot be a possible value 05 May 2021, 10:26
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chetan2u
Emdad
If x/y = 3/7, then which of the following cannot be a possible value of (y - x)?
(A) 4
(B) 21
(C) 24
(D) 84
(E) None of these


Now \(\frac{x}{y}\) is in simplified form, so let us take the common ratio to be a.
Thus x=3a and y=7a, y-x=7a-3a=4a.

So y-x will always be a multiple of 4.
21 is not a multiple of 4. Hence B

OA is wrong.
Show more

Notice that we are not told that x and y are integers. So, y - x can be 21 if x = 63/4 and y = 147/4. E is the answer.
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If x/y = 3/7, then which of the following cannot be a possible value 05 May 2021, 10:21
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Emdad
If x/y = 3/7, then which of the following cannot be a possible value of (y - x)?
(A) 4
(B) 21
(C) 24
(D) 84
(E) None of these
Show more


Now \(\frac{x}{y}\) is in simplified form, so let us take the common ratio to be a.
Thus x=3a and y=7a, y-x=7a-3a=4a.

So y-x will always be a multiple of 4.
21 is not a multiple of 4. Hence B

OA is wrong.
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If x/y = 3/7, then which of the following cannot be a possible value Updated on: 05 May 2021, 15:04
Originally posted by Emdad on 05 May 2021, 10:32.
Last edited by Emdad on 05 May 2021, 15:04, edited 1 time in total.
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Bunuel
chetan2u
Emdad
If x/y = 3/7, then which of the following cannot be a possible value of (y - x)?
(A) 4
(B) 21
(C) 24
(D) 84
(E) None of these


Now \(\frac{x}{y}\) is in simplified form, so let us take the common ratio to be a.
Thus x=3a and y=7a, y-x=7a-3a=4a.

So y-x will always be a multiple of 4.
21 is not a multiple of 4. Hence B

OA is wrong.

Notice that we are not told that x and y are integers. So, y - x can be 21 if x = 63/4 and y = 147/4.
Show more

Exactly, the official explanation is also mentioned that we are not sure whether x and y are integer or not so in this case all four options could be the answer.
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If x/y = 3/7, then which of the following cannot be a possible value 05 May 2021, 10:41
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Bunuel
chetan2u
Emdad
If x/y = 3/7, then which of the following cannot be a possible value of (y - x)?
(A) 4
(B) 21
(C) 24
(D) 84
(E) None of these


Now \(\frac{x}{y}\) is in simplified form, so let us take the common ratio to be a.
Thus x=3a and y=7a, y-x=7a-3a=4a.

So y-x will always be a multiple of 4.
21 is not a multiple of 4. Hence B

OA is wrong.

Notice that we are not told that x and y are integers. So, y - x can be 21 if x = 63/4 and y = 147/4.
Show more


Agreed Bunuel.

But then the question does not make sense. y-x can take any possible value, and there is no point in asking ‘ what cannot be a possible value?’
y-x can be 10, 34, 2.7654 etc

For example: y-x can be 1.5 ....4a=1.5....a=3/8.

So \(y=\frac{7*3}{8}=\frac{21}{8} \ \ and \ \ x=\frac{3*3}{8}=\frac{9}{8}\)......

\(y-x=(\frac{21}{8})-(\frac{9}{8})=\frac{12}{8}=1.5\)

So, either OA is wrong or the question is wrong.
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If x/y = 3/7, then which of the following cannot be a possible value 05 May 2021, 10:46
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chetan2u
Bunuel
chetan2u



Now \(\frac{x}{y}\) is in simplified form, so let us take the common ratio to be a.
Thus x=3a and y=7a, y-x=7a-3a=4a.

So y-x will always be a multiple of 4.
21 is not a multiple of 4. Hence B

OA is wrong.

Notice that we are not told that x and y are integers. So, y - x can be 21 if x = 63/4 and y = 147/4.


Agreed Bunuel.

But then the question does not make sense. y-x can take any possible value, and there is no point in asking ‘ what cannot be a possible value?’

y-x can be 1.5 also....4a=1.5....a=3/8.
So y=7*3/8 and x=3*3/8......
y-x=(21/8)-(9/8)=12/8=1.5
Show more

Well, I think this is exactly the point of this question. By the way, y - x cannot be 0.

Agree not very GMAT like.
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If x/y = 3/7, then which of the following cannot be a possible value 16 Aug 2023, 04:42
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Let x=15.75 and y=36.75 then the ratio is equal to 3/7 and y-x=21.. As it's not mentioned wheather they are intiger or not..

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If x/y = 3/7, then which of the following cannot be a possible value 04 Sep 2023, 07:03
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x/y = 3/7 = 3a/7a

So, y-x = 7a - 3a = 4a

It's not mentioned whether x or y is an integer or not.

So, if a=5.25, and we get (y-x)=21 as an answer.

E should be the answer.
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If x/y = 3/7, then which of the following cannot be a possible value 13 Sep 2024, 21:14
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