A mother is 5 times as old as her daughter. After 5 years her age will be 3 times that of her daughter. What is the mother's present age?

25 years

Let the age of daughter  = x 

Age of mother = 5x 

 after 5 years ,

according to question   

3 ( x + 5 ) = 5x + 5

3x + 15 = 5x + 5 

2x = 10 

x = 5 years

therefore age of mother = 5 × 5 = 25 years