TABLE 10-7 A Buyer for a Manufacturing Plant Suspects That His Primary

question 93

Short Answer

TABLE 10-7
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.
Primary Secondary
Material Supplier Supplier 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
Sum: $309 $292 $17
Sum of Squares: $17,573 $15,472 $139
-Referring to Table 10-7, what is the 90% confidence interval estimate for the mean difference in prices?

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Definitions:

Nucleic Acid

Organic molecules that serve as the blueprint for proteins and, through the actions of proteins, the entire phenotype of a living organism; includes DNA and RNA.

Hydrolysis

A chemical reaction in which water is used to break down the bonds of a particular substance, commonly involving the disassembly of polymers into monomers.

Nucleotides

The building blocks of DNA and RNA, consisting of a nitrogenous base, a sugar (ribose in RNA, deoxyribose in DNA), and one to three phosphate groups.

Pyrimidines

Nitrogenous bases, each composed of a single ring of carbon and nitrogen atoms (e.g., thymine, cytosine, and uracil); components of nucleic acids. Compare with purines.