Question 378058
let son be x years
father = y
...
y=9x
after 3 years
son = x+9
father = y+9
(y+9)=3(x+9)
plug value of y  =9x
(9x+9)=3x+27
9x+9=3x+27
-3x
9x-3x+9=27
6x+9=27
-9
6x=18
/6
x=3 son's age now
father's age = 9x = 27 years now
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m.ananth@hotmail.ca