In eight throws of a die 5 or 6 is considered a success, find the mean number of successes and the standard deviation.
Let p be the probability of success
∴ the p = probability of getting 5 or 6
Given, n = 8
Mean = np
= 2.66
Standard deviation = 
= 1.33
Therefore, mean = 2.66, standard deviation = 1.33.
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