Q11 of 99 Page 33

Mark the correct alternative in the following:

The least number of times a fair coin must be tossed so that the probability of getting at least one head is at least 0.8, is


Given:


P(atleast 1 head) = 0.8


n=?


p(H)=p(T) = 1/2


Required probability = p= 1-


P0.8





For n= 2



For n=3



So, n=3

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