Question 587274: Father: When I was your age, you were 3 years old.
Son: When I reach your age, you will be 63 years old.
What is the father's present age?
Found 2 solutions by Edwin McCravy, richwmiller:
Answer by Edwin McCravy(20056)   (Show Source):
You can put this solution on YOUR website! Father: When I was your age, you were 3 years old.
Son: When I reach your age, you will be 63 years old.
Suppose the Father is x years older than the son.
Then x years ago the Father was the Son's present age, and the son was 3.
F - x = S
S - x = 3
And x years from now the son will be the father's age and the father will
be 63.
S + x = F
F + x = 63
So we have this system:
F - x = S
S - x = 3
S + x = F
F + x = 63
The first and third equations are equivalent so we can ignore the
third equation:
F - x = S
S - x = 3
F + x = 63
Solve that system and you'll get F = 43, S = 23, x = 20
Checking: 20 years ago the father was 43-20 or 23, which is the son's present
age. 20 years ago the son was 23-20 or 3. 20 years from now the son will
be 23+20 or 43, the Father's present age, and 20 years from now the father will be 43+20 or 63.
Edwin
Answer by richwmiller(17219)  (Show Source):
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