Question

The average age of 20 boys in a class is 12 years. 5 new boys are admitted to the class whose average age is 7 years. The average age of the boys in the class becomes

• A. 9.5 years
• B. 8.2 years
• C. 11 years
• D. 12.5 years

Answer 1

Answer:

C. 11 years

New average age of class=20×12+5×7/25 =240+35/25 = 11 years