Subjective Type

A coin is tossed a times, what is the chance that the head will present itself an odd number of times?

Solution

As we know, n(S)=2100
n(E)= No. of favorable ways =100C1+100C3+...100C99=2100−1=299
[∵nC1+nC3+nC5+...........................=2n−1]
∴P(E)=
n(E)
n(S)

=
299
2100

=
1
2

SIMILAR QUESTIONS

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