A father is 60 years old and his son is half his age. how old was the boy when his father was four times his age?

Ok so

fater=60

son is 1/2

60 times 1/2=30

they aer 30 years apart

how long ago was father age 4 times son age

father's age x year ago=60-x

son's age x years ago=30-x

60-x=4 (30-x)

distribute

60-x=120-4x

add 4x to both sides

60+3x=120

minus 60 from both sides

3x=60

divide both sides by 3

x=20

20 years ago

30-20=10

the boy was 10 years old

He was 10 while his father was 40