SOLUTION: A father is now 3 times older than his son.12 years ago he was 6 times as old as his son.Find their present Ages

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Question 624211: A father is now 3 times older than his son.12 years ago he was 6 times as old as his son.Find their present Ages
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Let +f+ = father's age now
Let +s+ = Son's age now
+f+-+12+ = Father's age 12 years ago
+s+-+12+ = Son's age 12 years ago
given:
(1) +f+=+3s+
(2) +f+-+12+=+6%2A%28+s+-+12+%29+
----------------------
Substitute (1) into (2)
(2) +3s+-+12+=+6s+-+72+
Subtract +3s+ from both sides
(2) +-12+=+3s+-+72+
(2) +3s+=+72+-+12+
(2) +3s+=+60+
(2) +s+=+20+
and
(1) +f+=+3s+
(1) +f+=+3%2A20+
(1) +f+=+60+
The Father is 60 and the Son is 20
check:
(2) +f+-+12+=+6%2A%28+s+-+12+%29+
(2) +60+-+12+=+6%2A%28+20+-+12+%29+
(2) +48+=+6%2A8+
(2) +48+=+48+
OK