Questions:

A receiving clerk for a chemical-products distributor, faced with the continuing problem of broken glassware. The clerk has determined some additional shipping precautions that can be undertaken to prevent breakage, and he has asked the Purchasing Director to inform the suppliers of the new measures. Data for 8 suppliers are given below in terms of average number of broken items per shipment before and after the implementation of the new measures.

Supplier	1	2	3	4	5	6	7	8
Before	16	12	18	7	14	19	6	16
After	14	13	12	6	9	15	8	15

1. Do the data indicate, at = 0.05, that the new measures have lowered the average number of broken items? Test at another appropriate significance level.

2. State any assumptions you made in part (i)

3. Why independent sample t test is not the most appropriate test to use in part (i)?