A box has 15 green, 10 yellow balls.

Question

A box has 15 green, 10 yellow balls. 10 balls drawn one by one with replacement. Find the variance of the number of green balls drawn.

Accepted Answer

$p=\dfrac{15}{25}=\dfrac35$, $q=\dfrac25$, $n=10$.

$$\text{Var} = npq = 10\times\frac35\times\frac25=\frac{12}{5}$$

Solutions · 1