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
A) (mb + nc)/ (m + m) years  B) (mb + nc)/ (n + n) years  C) (mb + nc)/ (m + n) years  D) (mb + nn)/ (m + n) years  E) (mn + nc)/ (m + n) years
(mb + nc) / (m+ n)   Answer:(mb + nc)/ (m + n) years
<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?