Narendra's mother is four times as old as Narendra. Four years ago, his mother was six times as old as Narendra was. What are their Present ages?

Correct option is B

​Given:

Mother’s age = 4 ×  Narendra’s age.

Four years ago, Mother’s age = 6 × Narendra’s age.

Solution:
Let Narendra’s age = x
Mother’s age = 4x
Four years ago:

4x - 4 = 6(x - 4)

4x - 4 = 6x - 24 

2x = 20 

x = 10

Mother’s age = 4x = 40 years 

Thus, Narendra is 10 years old, and his mother is 40 years old.