Test the Claim That the Samples Come from Populations with the Same

question 59

Essay

Test the claim that the samples come from populations with the same mean. Assume that the populations are normally distributed with the same variance.
-A consumer magazine wants to compare the lifetimes of ballpoint pens of three different types. The magazine takes a random sample of pens of each type in the following table.
$\begin{array}{lll}\text { brandA }&\text {brand B }&\text {brand C }\\\hline260 & 181 & 238 \\218 & 240 & 257 \\184 & 162 & 241 \\219 & 218 & 213\end{array}$
Do the data indicate that there is a difference in mean lifetime for the three brands of ballpoint pens? Use $\text { Use } \alpha = 0.0$

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Definitions:

Price Increase

An adjustment made to the selling price of goods or services, often due to factors such as inflation, increased costs of production, or improvements in quality.

Percentage Change

A mathematical calculation that shows how much a quantity has increased or decreased as a proportion of its previous value.

Unit Sales

The quantity of items sold by a company, not taking into account the revenue from these sales.

Traceable Fixed Expense

A fixed expense that can be directly associated with a specific business segment or product.