If the average of n quantities is P and the average of m quantities is Q, then the average of (m + n) quantities is:

$\frac{nP+mQ}{m-n}$ $\frac{mP+nQ}{m+n}$ $\frac{nP+mQ}{P+Q}$ $\frac{nP+mQ}{m+n}$

$\frac{nP+mQ}{m+n}$

Sum of n quantities = nP Sum of m quantities = mQ Average of ( m + n ) = \(\frac{nP + mQ }{m + n }\)