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प्रश्न
Three coins are tossed together. Find the probability of getting exactly two heads
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उत्तर
When three coins are tossed once, the sample space is given by
S = {HHH, HHT, HTH, HTT, THH, THT, TTH, TTT}
i.e. n (S) = 8
Let E1 = event of getting exactly two heads
Then E1 = {HHT, HTH, THH}
i.e. n(E1) = 3
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