Question

Find the mean of the probability distribution

of random variable X, which can take only the

values

3, 5. and 7, given that P(3)=7/30, P(5)=10/30

and P(7)=13/30.

Answer 1

$M(X) = \sum {{x_i}} {p_i} = 3 \cdot \frac{7}{{30}} + 5 \cdot \frac{{10}}{{30}} + 7 \cdot \frac{{13}}{{30}} = \frac{{27}}{5}$

Answer: $\frac{{27}}{5}$