Q21 of 108 Page 271

Ten coins are tossed. What is the probability of getting at least 8 heads?

Let X be the random variable for getting a head.


Here, n=10, r≥8


r=8,9,10



We know that,


∴P(X=r) = P(r=8) + P(r=9)÷P(r=10)









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