What is the value of y?

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What is the value of y?

by kartikshah » Mon Jul 16, 2012 4:08 am
What is the value of y?
1. When y is multiplied by 6 the result is between 40 and 45
2. When y is multiplied by 3 the result is between 19 and 23


I chose the answer as D but the correct answer is E.

If y = 7 then 6*7 = 42 fulfils condition of statement 1
If y = 7 then 3*7 = 21 fulfils condition of statement 2
therefore only one unique value of y is possible !

Please explain
Thanks

Source: Princeton Review Practice Test 10

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by eagleeye » Mon Jul 16, 2012 4:57 am
kartikshah wrote:What is the value of y?
1. When y is multiplied by 6 the result is between 40 and 45
2. When y is multiplied by 3 the result is between 19 and 23


I chose the answer as D but the correct answer is E.

If y = 7 then 6*7 = 42 fulfils condition of statement 1
If y = 7 then 3*7 = 21 fulfils condition of statement 2
therefore only one unique value of y is possible !

Please explain
Thanks

Source: Princeton Review Practice Test 10
The question does not say that y is an integer. So 6.9, 6.99 are also solutions. Hence E.

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by dhairya275 » Mon Jul 16, 2012 4:58 am
Correct answer is E because we cannot assume 'y' to be an integer.

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by tisrar02 » Tue Jul 17, 2012 7:13 pm
I had 3 questions like this one when doing questions on the MGMAT. DO NOT UNDER ANY CIRCUMSTANCE ASSUME THAT NUMBERS HAVE TO BE INTEGERS... You will always get the wrong answer. Especially questions like this one. If you do the GMAT official prep question, there are questions like this one so beware!