# Question: If X is a random variable having a normal distribution

If X is a random variable having a normal distribution, what are the probabilities of getting a value

(a) Within one standard deviation of the mean;

(b) Within two standard deviations of the mean;

(c) Within three standard deviations of the mean;

(d) Within four standard deviations of the mean?

(a) Within one standard deviation of the mean;

(b) Within two standard deviations of the mean;

(c) Within three standard deviations of the mean;

(d) Within four standard deviations of the mean?

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