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प्रश्न
Three coins are tossed together. Find the probability of getting at least two heads
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 E2 = event of getting at least two heads
Then E2 = {HHH, HHT, HTH, THH}
i.e. n (E2) = 4
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