Question

How do you find the mean of the following probability distribution?

X P(X)
1 0.20
2 0.10
3 0.35
4 0.05
5 0.30

Answer 1

Mean is `3.15`

Explanation:

Mean of a probability distribution given by

`[(ulx,ul(P(x))), (1, 0.20), (2, 0.10), (3, 0.35), (4, 0.05), (5, 0.30)]`

is `(sum_i xP(x))/(sum_iP(x))`

And hence mean is

`(1xx0.20+2xx0.10+3xx0.35+4xx0.05+5xx0.30)/(0.20+0.10+0.35+0.05+0.30)`

= `(0.20+0.20+1.05+0.20+1.50)/1`

= `3.15`