Answer:
The hypothesis that the buyer should test is the paired t-test for the mean difference.
Step-by-step explanation:
We are given that a buyer for a manufacturing plant suspects that his primary supplier of raw materials is overcharging. To determine if his suspicion is correct, he contacts a second supplier and asks for the prices.
The data is given below;
Material Primary supplier Secondary supplier Difference
1 $55 $45 $10
2 $48 $47 $1
3 $31 $32 -$1
4 $83 $77 $6
5 $37 $37 $0
6 $55 $50 $5
7 $47 $40 $7
The hypothesis that the buyer should test is the paired t-test for the mean difference because we are interested in comparing the difference between the cost of raw materials charged by both the suppliers.