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Question
Determine P(E|F).
Two coins are tossed once, where
E: no tail appears, F: no head appears
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Solution
S = {HH, TH, HT, TT}
n(S) = 4
E: no tail appears,
E = {HH}
n(E) = 1
P(E) = `(n(E))/(n(S)) = 1/4`
F: no head appears
F = {TT}
n(F) = 1
P(F) = `(n(F))/(n(S)) = 1/4`
E ∩ F = Φ, n(E ∩ F) = 0, P(E ∩ F) = 0
P(E | F) = `(P(E ∩ F))/(P(F))`
`= 0/(1/4)`
= 0
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