The mean height of m boys and n girls in a school is a. If the mean height of the m boys is b, the mean height of the girls is ?
I think its a-b pls check

Question

The mean height of m boys and n girls in a school is a. If the mean height of the m boys is b, the mean height of the girls is ?
I think its a-b pls check

crashonce · Answer

@Directrix

crashonce · Answer

continue

crashonce · Answer

options: a-b, (A+B)/2, m/n (a+b)+a, m/n (a-b)+a, [am+an]/n -ma

directrix · Answer

I think what may be incorrect about your answer is that you assumed that the school had the same number of male students as female students. Just thinking that may be it.

directrix · Answer

@mathmath333   What is your take on this problem and what the answer is?

hartnn · Answer

mean height of m boys is b
so total height of m boys is mb.

The mean height of m boys and n girls in a school is a. 
so total height of m boys and n girls is (m+n)a

hartnn · Answer

so total height of n girls = (m+n)a - mb

hartnn · Answer

and their mean will be 

[(m+n)a -mb]/n

hartnn · Answer

a+ m/n (a-b)
is the in your options?
ask if any doubt in any step...