The expected value of the number obtained, on throwing a die having 2 written on three faces, 4 on two faces and 6 on one face, is : |
$\frac{3}{10}$ $\frac{10}{3}$ $\frac{8}{3}$ $\frac{3}{8}$ |
$\frac{10}{3}$ |
The correct answer is Option (2) → $\frac{10}{3}$ The expected value (Mean) of a discrete random variable X is, $E(X)=∑X.P(X)$ 2 appears on 3 face → Probability = $\frac{3}{6}=\frac{1}{2}$ 4 appears on 2 face → Probability = $\frac{2}{6}=\frac{1}{3}$ 6 appears on 1 face → Probability = $\frac{1}{6}=\frac{1}{6}$ $E(X)=\left(2×\frac{1}{2}\right)+\left(4×\frac{1}{3}\right)+\left(6×\frac{1}{6}\right)$ $=2+\frac{4}{3}=\frac{10}{3}$ |