The ratio of the ages of two persons is 4 : 7 and the age of one of them is greater than that of the other by 30 years. The sum of their ages (in years) is

(1) 110 (2) 100 (3) 70 (4) 40k

Solution:

Ages of the persons = 4x and 7x years.

:. 7x-4x=30 ⇒3x=30

⇒ x=10

:. Sum of their ages = 4x+7x

= 11x years

= 11*10= 110 years

Then the option is (1) 110