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Chapter 9: Q. 79 (page 589)

Pressing pills A drug manufacturer forms tablets by compressing a granular material that contains the active ingredient and various fillers. The hardness of a sample from each batch of tablets produced is measured to control the compression process. The target value for the hardness is μ=11.5. The hardness data for a random sample of 20tablets are

11.62711.61311.49311.60211.36011.37411.59211.45811.55211.46311.38311.71511.48511.50911.42911.47711.57011.62311.47211.531

Is there significant evidence at the5% level that the mean hardness of the tablets differs from the target value? Carry out an appropriate support your answer.

Short Answer

Expert verified

We do not have enough evidence to conclude that the hardness of these tablets is something other than 11.5.

Step by step solution

01

Given information

The hardness data for a random sample of 20tablets are

11.62711.61311.49311.60211.36011.37411.59211.45811.55211.46311.38311.71511.48511.50911.42911.47711.57011.62311.47211.531

02

Explanation

State: H0:μ=11.5,Ha:μ≠11.5

Plan: Random: Random sample.

Normal: The histogram indicates that the distribution is roughly symmetric with no outliers.

Independent: There are more than 200tablets.

Do:t=0.772,P-value=0.4494.

Conclude: Since the P-value is greater than 0.05, we fail to reject H0.

We do not have enough evidence to conclude that the hardness of these tablets is something other than 11.5.

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Most popular questions from this chapter

In planning a study of the birth weights of babies whose mothers did not see a

doctor before delivery, a researcher states the hypotheses as

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