A Company Claims That 9 Out of 10 Doctors (I

question 18

Multiple Choice

A company claims that 9 out of 10 doctors (i.e., 90%) recommend its brand of cough syrup to their patients. To test this claim against the alternative that the actual proportion is less than 90%, a random sample of 100 doctors was chosen which resulted in 83 who indicate that they recommend this cough syrup. The test statistic in this problem is approximately:

• A) -2.33
• B) 2.33
• C) -1.83
• D) -1.99

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Definitions:

Population Proportions

The percentage or fraction of individuals in a population that exhibit a particular attribute or characteristic.

Null Hypothesis

A hypothesis in statistical testing that there is no effect or no difference, and any observed deviation is due to sampling or experimental error.

Significance Level

A threshold below which a p-value is considered statistically significant, indicating that observed results are unlikely to be due to chance.

Critical Value

The point or points on the scale of a test statistic beyond which we reject the null hypothesis; these values define the threshold of significance.