Question

Probability distribution

Answer 1

Answer:

a) The value of q is 0.2.

b) E(X) = 1.85.

Step-by-step explanation:

Question a:

The sum of all the probabilities must be 1. So

$0.3 + x + 0.1 + 0.15 + 0.25 = 1$

$x + 0.8 = 1$

$x = 0.2$

The value of q is 0.2.

Question b:

Multiplication of each value of x by its probability. So

$E(X) = 0*0.3 + 1*0.2 + 2*0.1 + 3*0.15 + 4*0.25 = 1.85$

So the answer is E(X) = 1.85.