The mean and standard deviation measured from a randomly sel

The mean and standard deviation measured from a randomly selected sample of n = 42 mathematics SAT test scores are x = 680 and s = 35. Find an approximate 99 percent confidence interval for the population mean .

Solution

99% confidence occurs at 2.575 SD ,.

So,in our case

mean +-2.575 SD= answer

680+ 2.575*35>answer>680- 2.575*35

770.125>answer>589.875