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

question 47

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. At the 0.025 significance level,
test the claim that the four brands have the same mean if the following sample results have
been obtained. $$\begin{array} { c c c c } \text { Brand A } & \text { Brand B } & \text { Brand C } & \text { Brand D } \\\hline 17 & 18 & 21 & 22 \\20 & 18 & 24 & 25 \\21 & 23 & 25 & 27 \\22 & 25 & 26 & 29 \\21 & 26 & 29 & 35 \\& & 29 & 36 \\& & & 37\end{array}$$

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Definitions:

Ø30 f7 Fit

A specification for a cylindrical fit where Ø30 defines the nominal diameter in millimeters and f7 specifies the tolerance class for a hole.

High Precision Fit

Refers to a high degree of accuracy in the mating of two machine parts, ensuring minimal play or clearance between them.

H8/f7 Fit

A specific tolerance class designation for holes (H8) and shafts (f7) in engineering, ensuring a precise interference fit.

Basis

The underlying support or foundation for an idea, argument, or process; in materials, it could refer to the primary component or substance that forms the starting point.