Question

five years ago a man was seven times as old as his son. Five years hence the father will be three times as old as his son. find their present age.

Answer 1

Age of the son =x
Age of the father=7x
Present ages=x+5 and 7x+5
future age of the son=x+10
father=7x+10
7x+10=3(x+10)
x=5
7x=35
x+5=5+5=10
son age =10
father age =7x+5=7*5+5=40

Answer 2

Solution:-

letfather's age = x

son's age = y

5 years hence, age of father = x+5 

                                 

age of son = y+5

So (x+5) = 3(y+5)

⇒ x =3y+10

5 years ago, age of father = x-5 

                               

 age of son = y-5

So x-5 = 7(y-5)

⇒3y + 10 - 5 = 7y - 35

⇒ 4y = 40

⇒y = 10  age of son

   x = 3y +10 = 40

son age = 10 year

son age = 10 yearfather's age= 40 year

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@GauravSXena01