Question
If a coin tossed 15 times, what is the probability of getting head as many times in the first ten throws as in the last five?




None of these
easy
Solution
In the last five throws there can be 0, 1, 2, 3, 4, or 5 heads and the same should me in the first five throws.
Hence the favourable numbers of cases
.
And the total number of ways n = 2^{15 }= 32768.
Hence,
.
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