A researcher is interested in finding a 98% confidence interval for the mean number of times per day that college students text. The study included 121 students who averaged 25.9 texts per day. The standard deviation was 14.5 texts.Round answers to 3 decimal places where possible.

a. To compute the confidence interval use a?

t

z

distribution.

b. With98% confidence the population mean number of texts per day is betweenandtexts.

c.If many groups of 121 randomly selected members are studied, then a different confidence interval would be produced from each group. Aboutpercent of these confidence intervals will contain the true population number of texts per day and aboutpercent will not contain the true population mean number of texts per day.