After 6 years, the ratio of the ages of Arul to Karan is 7:6. The average age of Arul, Karan and Saran is 30 years

After 6 years, the ratio of the ages of Arul to Karan is 7:6. The average age of Arul, Karan and Saran is 30 years. If the age of Saran is 12 years younger than Arul, then find the present age of Karan?

A.            24 years

B.            30 years

C.            36 years

D.            42 years

E.            18 years

Sol:

Arul + Karan + Saran = 30 * 3 = 90

Arul – Saran = 12

Arul = 7x – 6

Karan = 6x – 6

Saran = 7x – 6 – 12

7x – 6 + 6x – 6 + 7x – 18 = 90

20x = 120

x = 6

Present age of Karan = 36 – 6 = 30 years