A random sample of 26 lunch orders at Noodles and Company sh

A random sample of 26 lunch orders at Noodles and Company showed a mean bill of $11.99 with a standard deviation of $4.68. Find the 95 percent confidence interval for the mean bill of all lunch orders.

The 95% confidence interval is from ______ to _______

Solution

Mean = 11.99

std deviation = 4.68

std error = 4.68/rt 26 = 0.2174

Margin of error = 1.8 or -1.8

95% confidence interval = (10.19, 13.79)