Probability problemSuppose that it is equally likely for a pregnancy to deliver a baby boy as it is to deliver a baby girl. Suppose that for a large society of people, every family continues to have children until they have a boy, then they stop having children. After 1,000 generations of families, what is the ratio of males to females?
:)
Heehee
P(1 M) = 0.5
P(1 F 1 M) = 0.5 ^2
P(2 F 1 M) = 0.5 ^3
...
E(Male) = 0.5 + 0.5 ^ 2 + 0.5 ^ 3 ... = 1
E(Female) = 0.5 ^ 2 + 2 * 0.5 ^ 3 + 3 * 0.5 ^ 4 = 1
P(1 F 1 M) = 0.5 ^2
P(2 F 1 M) = 0.5 ^3
...
E(Male) = 0.5 + 0.5 ^ 2 + 0.5 ^ 3 ... = 1
E(Female) = 0.5 ^ 2 + 2 * 0.5 ^ 3 + 3 * 0.5 ^ 4 = 1
Yeah!
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