A researcher is interested in finding a 95% confidence interval for the mean number of times per
day that college students text. The study
included 108 students who averaged 45.1 texts per
day. The standard deviation was 23.7 texts.
a. To compute the confidence interval use a 2 distribution.
?
b. With 95% confidence the population mean zber of texts per day is between
and
texts.
C. If Imany groups of 108 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 number of texts per day and about
will not contain the true population mean number of texts per day.
percent