Data sufficiency

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Data sufficiency

by ash4gmat » Thu Nov 12, 2015 9:26 am
Hi,

Came across this question. Can someone help understand the term "each of whom older than 1".Does this mean older by 1 year or older than each other?

Q)Ian has three pets: Barnum the cat, Bailey the cat, and Daisy the dog, each of whom is older than 1. If the product of their ages is x, and the product of x and 361 is 361,361, how old is Ian's dog Daisy?

(1) Daisy is not yet 10 years old.

(2) The sum of the digits of Barnum's age is even

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by [email protected] » Thu Nov 12, 2015 9:40 am
Hi ash4gmat,

Although the original author of this question did not put in the restriction that the ages are all INTEGERS, it appears that that is the "intent" of the question. The questions on the Official GMAT are always carefully worded though (to remove this type of ambiguity).

The statement that each of the pets is 'older than 1' means that each animal is at least 2 years old. Using prime factorization, we're meant to deduce that the ages of the pets are 7, 11 and 13 (in some order). We're asked for Daisy's age.

Fact 1: Daisy is not yet 10.

This means that she's YOUNGER than 10 and there's only one value that fits: 7
Fact 1 is SUFFICIENT

Fact 2: The sum of the digits in Barnum's age is EVEN.

This means that Barnum is either 11 or 13. In either situation, Daisy could be EITHER of the other two ages.
Fact 2 is INSUFFICIENT

Final Answer: A

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