Find the sum in reduced form.

25
2
5
+ 23
2
3
=
815
8
15
48
4
8
415
4
15
1 115

Arandom sample of 45 observations results in a sample mean of 68. the population standard deviation is known to be 23 a. compute the margin of error at a 959% confidence interval. b. compute the 95% confidence interval for the population mean c. compute the 90% confidence interval for the population mean. d. compute the 75% confidence interval for the population mean