緊急!!!) 機會率

A:

P(無次品)

= (1 - 4%)^5

= 0.96^5

= (24/25)^5

= 7962624 / 9765625

=0.815372697

B:

P(有2個以下次品)

= P(無次品) + P(有1個次品)

= 0.815372697 + 5*(4%)(1 - 4%)^4

= 0.815372697 + 0.169869312

=0.985242...

2009-11-04 14:23:51 補充：
^ 即係次方,例如

2^2 = 2*2 = 4

3^4 = 3*3*3*3 = 81

Hope this help!

^ 係指....??