SOLUTION: The ratio of a boy�s age to his father�s age is 1 : 4. In 4 years� time, the ratio of their ages will be 1 : 3. How old is the boy now?

Question 614316: The ratio of a boy�s age to his father�s age is 1 : 4. In 4 years� time, the ratio of their ages will
be 1 : 3. How old is the boy now?
Found 2 solutions by mananth, josmiceli:
Answer by mananth(16946) (Show Source): You can put this solution on YOUR website!
boy's age be x
and father's age =y

so y= 4x
In 4 years their ages will be
x+4 & y+4

cross multiply
3(x+4) = (y+4)
substitute y
3x+12=4x+4
4x-3x=12-4
x=8 the boy's age

Answer by josmiceli(19441) (Show Source): You can put this solution on YOUR website!
Let = boy's age now
Let = Father's age now
given:
(1)
(2)
--------------------------
(1)
By substitution:
(2)
(2)
(2)
(2)
and
(1)
(1)
(1)
The boy is 8 now
check:
(2)
(2)
(2)
(2)
(2)
OK
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