A psychologist has designed a psychotherapy program for people suffering from obesity and wanted to determine what the mean weight loss would be for a population of people with obesity following the program. The weight loss in kilograms of 13 people who suffered from obesity and participated in the program were randomly selected, and the results were as follows: 21.4 23.1 25.9 24.7 23.4 24.5 21.9 25.0 22.5 29.9 29.4 25.8 23.2 Question 15: Calculate and interpret a 90% confidence interval for the mean weight loss of the population of obese people following the program (rounded off to two decimals). Question 16: The psychologist claims that obese people participating in her psychotherapy program will have an average weight loss of more than 20.5 kilograms. Test the psychologist's claim at a 1% level of significance (rounded off to two decimals).
Added by Mary R.
Step 1
4 + 23.1 + 25.9 + 24.7 + 23.4 + 24.5 + 21.9 + 25.0 + 22.5 + 29.9 + 29.4 + 25.8 + 23.2) / 13 = 24.08 s = √[(1/12) * ((21.4-24.08)^2 + (23.1-24.08)^2 + ... + (23.2-24.08)^2)] = 2.44 Show more…
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