Question

Given that X ~ B(n= 10, p). If E(X) = 8 then the value of

p is ...........

(a) 0.6

(b) 0.7

(c) 0.8

(d) 0.4

Answer 1

(c)

Since X ~ B(n = 10, p),
E(x) = np
10p = 8
p = 0.8