Explain why the experiment of tossing a coin three times is said to have binomial distribution.

As the random variable X takes

   

is said to be binomial distribution having parameters n and p, if the probability is given by

P(X = r) =

   

where

   

and r =

   

Similarly, in case of tossing a coin

   

 times, we have

n = 3 and X has the values

   

 with p =

   

, q =

   

.