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

question 26

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 90% confidence interval estimate for the mean difference in prices?

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Definitions:

Nonhuman Animals

Living organisms that are not human beings, often referred to in contexts of biological, psychological, or ethical studies.

Mental Age

An assessment of an individual's mental development as compared to the norms for their chronological age.

Mental Development

Refers to the cognitive growth and progression in understanding, problem-solving, and decision-making abilities throughout a person's life.

Mental Ability

The capacity to perform cognitive tasks, process information, and understand concepts through various mental faculties like reasoning, memory, and problem-solving.