Using the binomial distribution, it is found that the mean and the standard deviation of variable x are given as follows:
[tex]\mu = 3, \sigma = 0.87[/tex]
It is the probability of exactly x successes on n repeated trials, with p probability of a success on each trial.
The expected value of the binomial distribution is:
E(X) = np
The standard deviation of the binomial distribution is:
[tex]\sqrt{V(X)} = \sqrt{np(1-p)}[/tex]
In this problem, we have that the parameters are given as follows:
n = 4, p = 0.75.
Hence the mean and the standard deviation are given as follows:
More can be learned about the binomial distribution at https://brainly.com/question/24863377
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