I donot agree with the reasoning. What is the ratio of y to

[amateur]

What is the ratio of y to x?

(1) y = 3x

(2) x = 11


The ratio of y to x can be expressed as a fraction, so the rephrased question is "what is y / x?"

EXPLANATION:
(1) SUFFICIENT: This statement gives y in terms of x. Substituting for y in the rephrased question, we get y / x = 3x / x = 3. The ratio of y to x is 3.

(2) INSUFFICIENT: This statement gives a value for x. Substituting for x in the rephrased question, we get y / x = y / 11. The ratio of y to x is y / 11, which could be any value, depending on the value for y. Since we don’t know the value of y, this statement is insufficient.

The correct answer is A.

I went with 'C'. y to x ratio is undefined when x is zero. The question did not mention whether x is nonzero. (2) by stating x=11 clarified that x is nonzero and so y/x can be 3.

[RonPurewal]

What is the ratio of y to x?

(1) y = 3x

(2) x = 11


The ratio of y to x can be expressed as a fraction, so the rephrased question is "what is y / x?"

EXPLANATION:
(1) SUFFICIENT: This statement gives y in terms of x. Substituting for y in the rephrased question, we get y / x = 3x / x = 3. The ratio of y to x is 3.

(2) INSUFFICIENT: This statement gives a value for x. Substituting for x in the rephrased question, we get y / x = y / 11. The ratio of y to x is y / 11, which could be any value, depending on the value for y. Since we don’t know the value of y, this statement is insufficient.

The correct answer is A.

I went with 'C'. y to x ratio is undefined when x is zero. The question did not mention whether x is nonzero. (2) by stating x=11 clarified that x is nonzero and so y/x can be 3.

hi amateur,

your objection here is valid, in one sense: yes, there should be a statement that x and/or y is nonzero.

on the other hand, you can rest easy about encountering this sort of thing on the real exam.
when an official DS statement is insufficient, it will never be insufficient because it is undefined in one case but defined in another. ALL official statements that are "insufficient" will actually allow you to find two different concrete answers.

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is this problem from our CAT exams? i can't find it in our database. (if it's not, then this post shouldn't be in the current folder and will be deleted or moved shortly.)

if you saw this problem on our CAT exams, please let me know, thanks.

[amateur]

Hello Ron,

Thanks for responding. Yes this problem is from MGMAT CAT exam. If I am not wrong, Manhattan has access to my profile. Please go ahead and check my CAT exams. It is the third question from my first CAT exam. In any case, I am also attaching a snapshot of this question. Please let me know if you need any.

Thanks.

[tim]

I can confirm that this problem is in our database. Looks like they just left off a piece of information that, as Ron says, would never be left off on the actual GMAT. Good catch, but don't worry too much about it.