The average of p, q, r is 12, then what will be the average of r and s?

48

Average = $\frac{sum\; of\; numbers}{quantity}$

$\frac{p+q+r+s}{4}$ = 30   -------(i)

We also know. average of p and q = 12

⇒ $\frac{p+q}{2}$ = 12

⇒ p + q = 12 x 2 = 24   ---------------(ii)

Putting the value of p and q in eq(i)

$\frac{24+r+s}{4}$ = 30

24 + r + s = 120

r + s = 96

Average of r and s = $\frac{r+s}{2}$ = $\frac{96}{2}$ = 48