Question

A father is four times as old as his son . in four years time ; he will be three times as old as his son . what are their present ages?

Answer 1

present age

let the sons age be x

then fathers age= 4x

after 4years

sons age= x+4

fathers age = 4x+4

but given after 4 years

sons age = x+4

fathers age = 3(x+4)

4x+4 = 3(x+4)

4x+4 = 3x+ 12

4x-3x=12-4

x=8

4x= 4*8

   =32

therefore present age of son is 8 years and father  is 32 years

Answer 2

Father=x

Son=y

Given

x=4y

x+4=3(y+4)

x+4=3y+12

x=3y+8

4y=3y+8

y=8

x=4y=4*8=32