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प्रश्न
If three coins are tossed simultaneously, find the probability of the following events.
Event B: To get at least two heads.
उत्तर
Sample space,
S = {HHH, HHT, HTH, THH, HTT, THT, TTH, TTT}
∴ n(S) = 8
Let B be the event of getting at least two heads
∴ B = {HHH, HHT, HTH, THH}
∴ n(B) = 4
∴ P(B) = `("n"("B"))/("n"("S"))`
∴ P(B) = `4/8`
∴ P(B) = `1/2`
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