Question

A processor of carrots cuts the green top off each carrot, washes the carrots, and inserts six to a package. Twenty packages are inserted in a box for shipment. To test the mass of the boxes, a dew were checked, the mean mass was 9.3 kg, the standard deviation 0.23 kg. How many boxes must the professor sample to be 95 percent confident that the sample mea does not differ from the population mean by more than 0.09 kg?