A small computing center has found that the number of jobs s

A small computing center has found that the number of jobs submitted per day to its computers has a
distribution that is approximately bell-shaped and symmetric, with a mean of 76 jobs and a standard
deviation of 5. Where do we expect most (approximately 95%) of the distribution to fall?
A) between 61 and 91 jobs per day
B) between 71 and 81 jobs per day
C) between 66 and 86 jobs per day
D) between 86 and 91 jobs per day

Solution

For normal distribution, 95% of the data is between 2 standard deviations above and below the mean.

Thus, it is between

u - 2s < x < u + 2s

76 - 2*5 < x < 76 + 2*5

66<x<86 [OPTION C, ANSWER]