A father is four times as old as his son is. Five years back he was seven times as old as his son was then. What is the present age of the father?Correct answer is '40'. Can you explain this answer?

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A father is four times as old as his son is. Five years back he was seven times as old as his son was then. What is the present age of the father?

Correct answer is '40'. Can you explain this answer?

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A father is four times as old as his son is. Five years back he was se...

Let the age of the son and father be x and y respectively. 5 years back, their ages were (x-5) and (y-5)
According to the given conditions
4x = y 4x-y = 0 ...(1)
7(x-5) = (y-5) 7x - 35
= y -5 7x -y = 30 ...(2)
Subtracting (1) from (2),
we get 7x - y - 4x + y = 30 - 0 3x = 30 x = 10 years
y = 4*10 = 40 years
The present age of the father is 40 years.

Answered by Talent Skill Learning · View profile

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