Answer:
Step-by-step explanation:
Using this table, the critical value for the 90% confidence level is 1.645 (note: look in the row that starts with infinity and look for the value above 90%)
So z = 1.645
Given Information:
n = 40
s = 32
A hospital emergency room has collected a sample of n = 40 to estimate the mean number of visits per day. It has found the standard deviation is 32. Using a 90 percent confidence level, what is its margin of error?
-------------
sample mean:: x-bar = 40
ME = 1.645(32/sqrt(40)) = 8.32
