Question 1201963
population mean is 800
population standard deviation is 50
sample size is 3
since you are looking for the mean of a sample, use the standard error rather than the standard deviation.
standard error = standard deviation / sqrt(sample size) = 50 / sqrt(3) = 28.86751346.
probability that the number of words per page in the sample is not between 830 and 845 is equal to .9102
here's what it looks like on a normal distribution calculator.
<img src = "http://theo.x10hosting.com/2023/042801.jpg">