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
[tex]0.3 + x + 0.1 + 0.15 + 0.25 = 1[/tex]
[tex]x + 0.8 = 1[/tex]
[tex]x = 0.2[/tex]
The value of q is 0.2.
Question b:
Multiplication of each value of x by its probability. So
[tex]E(X) = 0*0.3 + 1*0.2 + 2*0.1 + 3*0.15 + 4*0.25 = 1.85[/tex]
So the answer is E(X) = 1.85.