The average age of M boys is ‘b’ years and of ‘n’ girls ‘c’ years. The average age of all together is? Choose the correct choice from the following answers
A) (mb + nc) / (m+ m) B) (mb + nc) / (n+ n) C) (mb + nc) / (m+ n) D) (mb + nm) / (m+ n) E) (mb + nc) / (m+ n)
(mb + nc) / (m+ n)   Answer: (mb + nc) / (m+ n)
<result>C</result>
The average age of M boys is ‘b’ years and of ‘n’ girls ‘c’ years. The average age of all together is?