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 + n) years	B) (mb + nc)/ (m - n) years	C) (mb + nc)/ (m + n) years	D) (mb – nc)/ (m - n) years	E) (mn – mc)/ (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?