Q10 of 99 Page 33

Mark the correct alternative in the following:

A fair coin is tossed 99 times. If X is the number of times heads occur, then P(X = r) is maximum when r is


Given:


n=99


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


P(x=r)= nCr pr qn-r


P(x=r)= nCr pn


nCr =


Its maximum value is closest near n/2


Since n is an odd number, so it have two values:


i.e.


S0, r= 49,50

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