Question

What is john present age if after 10 years his age will be 5 times his age 5years back

Answer 1

Define x:

Let John be x years old now.

10 years later:

John = x + 10

5 years ago:

John = x - 5

His age 10 years later will be 5 times his age 5 years ago:

x + 10 = 5(x - 5)

Solve x:

x + 10 = 5(x - 5)

x + 10 = 5x - 25

4x = 35

x = 8.75 years old (or 8 years 9 months old)

Answer: John's present age is 8.75 years old