Question

robert's father is 4 times as old as robert. after 5 years, father will be tree times as old as robert. find the their present age

Answer 1

Let,
Robert's age = x years
Age of Robert's father = 4x years

========================
After 5 years,

Robert's age = (x + 5) years
Age of Robert's father = (4x + 5) years

According to the question,

4x + 5 = 3(x + 5)

=> 4x + 5 = 3x + 15

=> 4x - 3x = 15 - 5

=> x = 10

Then,

Present age of Robert = x = 10 years
Present age of father = 4x=40 years



I hope this will help you


-by ABHAY