<PRE><B>Question 524218</B>
Your present age = 8
Yours Dad = 41

Let
It takes = x years

After x years 
your Dad will be = 41+x
You will be = 8+x
Then
Your Dad will be twice of your age
2(8+x)=41+x
16+2x=41+x
2x-x=41-16
x=25

After 25 years your Dad will be twice of your age.

Check
=====
After 25 years you will be = 8+25=33
After 25 years your Dad will be = 41+25=66


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