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Question
Explain why the experiment of tossing a coin three times is said to have binomial distribution.
Solution
We know that random variable X takes values 0, 1, 2, 3, ..., n is said to be binomial distribution having parameters n and p
If the probability is given by
P(X = r) = `""^"n""C"_"r" "p"^"r" "q"^("n" - "r")`
Where q = 1 – p and r = 0, 1, 2, 3, ...
Similarly in case of tossing a coin 3 times,
n = 3 and X has the values 0, 1, 2, 3 with p = `1/2`, q = `1/2`.
Hence, it is said to have a binomial distribution.
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