[問題]OG(11th)PS-Q231

[凱薩琳]

Xavier, Yvonne, and Zelda each try independently to solve a problem. If their individual probabilities for success are 1/4, 1/2, and 5/8, respectively, what is the probability that Xavier and Yvonne, but not Zelda, will solve the problem?

(A)11/8
(B)7/8
(C)9/64
(D)5/64
(E)3/64

Ans:E

[scujean]

[解]問X和y成功且同時z失敗于解決問題的機率，
P（x成功）*p（y成功）*p（z失敗）=[1/4][1/2][3/8]

[凱薩琳]

原來這麼簡單阿..是我想太複雜了..謝謝