# A Boy and his friend age riddle

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A man is as old as his friend will be when the man is twice the age that the friend was
when the man’s age was half the sum of their present ages.

What are their ages?

SherlockHolmes Expert Asked on 25th December 2017 in

TWO Possible answers: (NOT considering ‘fraction ages’ such as X years and Y months and ‘improbable ages’ such as above 120 years)

(1) The man is 40 and his friend is 30
Sum of their ages = 40 + 30 = 70.
When the man’s age was half the sum of their present ages, he was 70 / 2 = 35 (i.e. 5 years ago).
At that time, his friend was 25. When the man is twice this age (the age his friend was when the man was 35), he (the man) would be 25 x 2 = 50 (i.e., 10 years from now.) By that time, his friend (who is 30 now) will have turned 30 + 10 = 40, which is as old as the man is now.

(2) The man is 80 and his friend, 60
Sum of ages = 140.
When the man’s age was half the sum of their present ages, he was 140 / 2 = 70 (i.e. 10 years ago).
At that time, his friend was 50. When the man is twice this age (the age his friend was when the man was 70), he (the man) would be 50 x 2 = 100
(i.e., 20 years from now.) By that time, his friend (who is 60 now) will have turned 60 + 20 = 80, which is as old as the man is now.

If we consider fraction ages, there can be multiple possible answers (fractions of the above-said figures. e.g. 20 and 15, 60 and 45 etc.)

Viji_Pinarayi Expert Answered on 25th December 2017.

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