Question

3. Raju’s father is 7 times as old as Raju. After 10 years he will be three times as old as his son. Find their present ages. 

Answer 1

let raju's age be x, then his father's age will be 7x.
after 10 years, raju's age will be x+10 and his father's age will be 7x+10.
after 10 years raju's father will be his 3 times, i.e. :
7x+10= 3(x+10)
=7x+10= 3x+30
=7x-3x=30-10
=4x=20
=x=20/4
=5
therefore raju's age is 5 years and his father's age is 7x i.e. 7*5= 35

Answer 2

Answer:

let raju's age be x, then his father's age will be 7x.

after 10 years, raju's age will be x+10 and his father's age will be 7x+10.

after 10 years raju's father will be his 3 times, i.e. :

7x+10= 3(x+10)

=7x+10= 3x+30

=7x-3x=30-10

=4x=20

=x=20/4

=5

therefore raju's age is 5 years and his father's age is 7x i.e. 7*5= 35

hope it is correct