a choir group has 80 people, they need to choose 20 people for a new group, someone who calls Patrick said he wanted to join with his friend. what is the probability i haven't learnt it so i don't know whether there is about the structute wrong
I think there isn't enough information. what is the probability------------> of what? Patrick said he wanted to join with his friend--------> how many friends? Is Patick one of the member of choir??
原帖由 JOHNLAM17 於 4/5/2006 19:31 發表 I think there isn't enough information. what is the probability------------> of what? Patrick said he wanted to join with his friend--------> how many friends? Is Patick one of the member ...
how many friend? 1 what is the probility? i mean u need to find the number because i haven't learnt it yet so i don't know how to write it sorry
80 ppl -> 4 groups P(both in group 1) = (1/4)(1/4)=1/16 P(both in group 2) = (1/4)(1/4)=1/16 P(both in group 3) = (1/4)(1/4)=1/16 P(both in group 4) = (1/4)(1/4)=1/16
P(both in the same group) = (1/16)(4)=1/4
correct ma....
原帖由 kazuhiko 於 5/5/2006 14:54 發表
做咩要乘四？
應該係 Required probobility = (20/80) x (19/79) =19/316
原帖由 hinchun34 於 4/5/2006 16:36 發表 a choir group has 80 people, they need to choose 20 people fora new group, someone who calls Patrick said he wanted to join with his friend. what is the probability i haven't learnt it so i don ...
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