Question

To better understand the fear that some adult patients experience when going to a dentist, a survey questionnaire has been used. Scores are reported on a scale of 0-25. Years of historic data has resulted in a mean of 15 and assumed standard deviation of 4. A researcher is interested in whether age is a factor in adult dental anxiety, specifically if anxiety lessens as we get older. At a=0.05, conduct a test of hypothesis to determine if the mean score of senior citizens is less than the assumed mean. A random sample of 40 senior citizens were given the survey, resulting in a sample mean score of 13.9.

Use the 5-step method:

Answer 1

TOPIC:Test for the population mean.