Q:

A student wanted to construct a 95% confidence interval for the mean age of students in her statistics class. She randomly selected nine students. Their mean age was 19.1 years, with a sample standard deviation of 1.5 years. What is the 95% confidence interval for the population mean?

Accepted Solution

A:
Answer:95% confidence interval for the population mean is 20.255 and 17.945Step-by-step explanation:given data mean = 19.1standard deviation = 1.5n = 9to find out95% confidence interval for the population meansolution we know 95% confidence interval formula i.e.mean +/- t * standard deviation/[tex]\sqrt{n}[/tex] Β  .............1here t for 9 students 2.31 ( from t table)so put all value n t standard deviation and mean in equation 1 = mean +/- t * standard deviation/[tex]\sqrt{n}[/tex] = 19.1 +/- 2.31 * 1.5/[tex]\sqrt{9}[/tex] = 19.1 +/- 2.31 * 1.5/[tex]\sqrt{9}[/tex] Β = 20.255 and 17.945 95% confidence interval for the population mean is 20.255 and 17.945