A researcher is interested in finding a 95% confidence interval for the mean number minutes students are concentrating on their professor during a one hour statistics lecture. The study included 136 students who averaged 33.6 minutes concentrating on their professor during the hour lecture. The standard deviation was 11.5 minutes.
a. To compute the confidence interval use a ? t z distribution.
b. With 95% confidence the population mean minutes of concentration is between and minutes.
c. If many groups of 136 randomly selected members are studied,
then a different confidence interval would be produced from each
group. About percent of these confidence intervals will
contain the true population mean minutes of concentration and
about percent will not contain the true population mean
minutes of concentration.
a. To compute the confidence interval use a t distribution.
b. With 95% confidence the population mean minutes of concentration is between 31.650 and 35.550 minutes.
c. If many groups of 136 randomly selected members are studied, then a different confidence interval would be produced from each group. About 95 percent of these confidence intervals will contain the true population mean minutes of concentration and about 5 percent will not contain the true population mean minutes of concentration.
Get Answers For Free
Most questions answered within 1 hours.