A weighted coin is flipped three times with P(H)=1/3.What is the probability that heads come out exactly twice given heads come out at least once?

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AweightedcoinisflippedthreetimeswithP(H)=1/3.Whatistheprobabilitythatheadscomeoutexactlytwicegivenhe

A weighted coin is flipped three times with P(H)=1/3.What is the probability that heads come out exactly twice given heads come out at least once?
A weighted coin is flipped three times with P(H)=1/3.What is the probability that heads come out exactly twice given heads come out at least once?

A weighted coin is flipped three times with P(H)=1/3.What is the probability that heads come out exactly twice given heads come out at least once?
得到0个head的几率是 1*1/3的零次方*2/3的三次方=8/27
得到2个的几率是 3*1/3的二次方*2/3的一次方=2/9=6/27
6/(27-8)=2/7
不懂的话可以追问

亲你们还没学完probability么……我们都考完final了……初步估计是用P(A | B)=P(A and B)/P(A)和binomial pdf、binomial cdf的公式,你要是不急我就把题抄下来明天问老师