A = player selected has a number from 1 to 8
B = player selected is a guard
C = player selected is a forward
D = player selected is a starter
E = player selected is a center
P(A) = 8/10 = 0.8
P(B) = 4/10 = 0.4
P(C) = 4/10 = 0.4
P(D) = 5/10 = 0.5
P(E) = 2/10 = 0.2
We need to find the complement for the two events: not guard nor forward.
P(B') = 1 - P(B) = 1 - 0.4 = 0.6 ⇒ {5, 6, 7, 8, 9, 10}
P(C') = 1 - P(C) = 1 - 0.4 = 0.6 ⇒ {1, 2, 3, 4, 9, 10}
P(B' and C') = P(B') × P(C') = 0.6*0.6 = 0.36
The probability of a player who is not a guard nor forward is about 0.36. This one you multiply because we are looking at events, not necessarily players themselves.