TABLE 10-8
a Buyer for a Manufacturing Plant Suspects That

question 174

Short Answer

TABLE 10-8
A buyer for a manufacturing plant suspects that his primary supplier of raw materials is overcharging. In order to determine if his suspicion is correct, he contacts a second supplier and asks for the prices on various identical materials. He wants to compare these prices with those of his primary supplier. The data collected is presented in the table below, with some summary statistics presented (all of these might not be necessary to answer the questions which follow). The buyer believes that the differences are normally distributed and will use this sample to perform an appropriate test at a level of significance of 0.01.
$\begin{array}{crrr}&\text { Primary}&\text { Secondary }\\\underline{\text {Material }}&\underline{\text {Supplier}}&\underline{\text { Supplier }}&\underline{\text {Difference }}\\1 & \$ 55 & \$ 45 & \$ 10 \\2 & \$ 48 & \$ 47 & \$ 1 \\3 & \$ 31 & \$ 32 & -\$ 1 \\4 & \$ 83 & \$ 77 & \$ 6 \\5 & \$ 37 & \$ 37 & \$ 0 \\6 & \$ 55 & \$ 54 & \$ 1 \\\hline \text { Sum: } & \$ 309 & \$ 292 & \$ 17\\\text { Sum of Squares: } &\$ 17,573& \$ 15,472 &\$ 139\end{array}$



-Referring to Table 10-8, what is the 95% confidence interval estimate for the mean difference in prices?

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Definitions:

Caring For Children

The act and practice of nurturing, looking after, and ensuring the growth, health, and safety of children.

Equal Work

The concept that work of equal value by different workers should receive the same pay and conditions.

Mania

A mental state characterized by excessively high energy levels, euphoria, and impulsiveness, often seen in bipolar disorder.

Antisocial Conduct

Behavior that goes against the norms of society, often violating the rights of others, possibly indicative of antisocial personality disorder.