Suppose the number of hours students study per week follows a normal distribution with a mean of 50 hours and a standard deviation of 2.1 hours. (a) Approximately what percentage of students study between 45.8 and 54.2 hours per week? 51% 68% 99.7% 95%
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We are given that $X$ follows a normal distribution with a mean $\mu = 50$ hours and a standard deviation $\sigma = 2.1$ hours. We want to find the percentage of students who study between 45.8 and 54.2 hours per week, which is $P(45.8 \le X \le 54.2)$. Show more…
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