Age question: Is this right?

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Age question: Is this right?

by datonman » Sun Sep 27, 2015 6:49 pm
If Janet is n years old, Karen is two years younger than Janet, and Mary is four years more than twice Janet's age, which of the following represents how many years older Mary is than Karen?

A. 2
B. n - 2
C. n
D. n + 2
E. n + 6

I came up with a possible answer to this question myself and it goes like this:

Janet = n
Karen = J - 2 or n - 2
Mary = 4 + 2J or 4 + 2n

Then:

n - 2 = 4 + 2n
+ 2 +2

n = 6 + 2n
-n -n

The answer I got is n + 6

Is this right or is there another approach to this problem?
Source: — Problem Solving |

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by [email protected] » Sun Sep 27, 2015 9:04 pm
Hi datonman,

This question can also be solved by TESTing VALUES.

We're told that Janet is N years old.

IF....

Janet = N = 3

Karen is 2 years younger than Janet....
Karen = 3 - 2 = 1

Mary is four years more than twice Janet's age...
Mary = 4 + 2(3) = 10

We're asked how much older Mary is than Karen....

Mary = 10
Karen = 1
Mary is 10 - 1 = 9 years older than Karen

So we're looking for an answer that equals 9 when N = 3. There's only one answer that matches....

Final Answer: E

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