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Question
If two coins are tossed, then find the probability of the event that at least one head turns up.
Solution
Let S be the sample space.
Then S = {HH, HT, TH, TT}
∴ n(S) = 4
Let A be the event where at least one tail turns up.
At least one head means 1 head or more than 1 heads.
If S = {HH, HT, TH, TT}
∴ A = {HT, TH, HH}
∴ n(A) = 3
n(A) 3
Now, ` P(A)=(n(A))/(n(s))=3/4`
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