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The question is

Jack is now 14 years older than Bill. If in 10 years Jack will be twice as old as Bill , how old will Jack be in 5 years? (Ans=23)

Here is how I am solving it could anyone tell me where I might be going wrong ?

$J = 14 + B$-->i

and $J+10 = 2B$-->ii

So inserting (i) in (ii) we get

$24=B$ so Jack is $38$ and after 5 years he will be $38+5=43$ years old

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The RHS in ii should be $2(B+10)$. – user2468 Sep 14 '12 at 1:14
In future, please use > instead of >>. – user2468 Sep 14 '12 at 1:16
up vote 3 down vote accepted

In your second equation, you are ten years in the future. With $J$ and $B$ representing Jack and Bill's present age respectively, Bill's age ten years from now is $B+10$ and Jack's age ten years from now is $J+10$. In your second equation, you had the latter term correct but not the former. Your second equation should be $J+10=2(B+10)$.

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Oh yes. Silly mistake on my part. Thanks for pointing it out – MistyD Sep 14 '12 at 1:16

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