# Question

The amount of time devoted to studying statistics each week by students who achieve a grade of A in the course is a normally distributed random variable with a mean of 7.5 hours and a standard deviation of 2.1 hours.

a. What proportion of A students study for more than 10 hours per week?

b. Find the probability that an A student spends between 7 and 9 hours studying.

c. What proportion of A students spend fewer than 3 hours studying?

d. What is the amount of time below which only 5% of all A students spend studying?

a. What proportion of A students study for more than 10 hours per week?

b. Find the probability that an A student spends between 7 and 9 hours studying.

c. What proportion of A students spend fewer than 3 hours studying?

d. What is the amount of time below which only 5% of all A students spend studying?

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