f1Need part b got 3.6147 8.7853 wrong You are interested in finding a 98% confidence interval for the average number of days of classthat college students miss each year. The data below show the number of missed days for 15randomly selected college students. Round answers to 3 decimal places where possible.|90|11| 5 8 8 5 5 10 12 3 4 3 4 6a. To compute the confidence interval use a ?distribution.b. With 98% confidence the population mean number of days of class that college students missis betweenanddays.c. If many groups of 15 randomly selected non-residential college students are surveyed, then adifferent confidence interval would be produced from each group. Aboutpercent ofthese confidence intervals will contain the true population mean number of missed class daysand aboutpercent will not contain the true population mean number of missed classdays.

We have to obtain confidence interval for average number of days of class that college students miss each year using the given 15 random sample units as:x901158855101234346where, x denotes the number of days college missed by the students.(a)As the value of population standard deviation is unknown and the sample size is also small(less than 30), t-distribution is used for obtaining the confidence interval of the true population mean.Calculation table for obtaining the values of sample statistics is obtained as:x 90-6.238.44114.823.045-1.21.4481.83.2481.83.245-1.21.445-1.21.44103.814.44125.833.643-3.210.244-2.24.843-3.210.244-2.24.846-0.20.04The sample mean of the given dataset is obtained as:Sample mean value is obtained as .The value of sample standard deviation using the given dataset is obtained as:Sample standard deviation is obtained as .The level of significance is obtained as:Degree of freedom for the test is obtained as:The two-tailed critical value for the test is obtained using the MS-excel formula "=TINV( )" and the two tailed critical value for t-distribution is obtained as:The 98% confidence interval for population mean is obtained as:The 98% confidence interval for the population mean number of days college missed by students is obtained as days.The 98% confidence interval can be interpreted as if the same experiment is repeated large number of times and confidence interval is obtained for each sample case, 98% of the times, the value of population mean will lie within this interval and 2% chances that the population mean will lie outside this.Therefore, the correct answer will be:If many groups of 15 randomly selected college students are surveyed, about the 98% of these confidence interval will contain the true population mean number of missed class days and of these will not contain the true population mean number of missed class days.a. To compute a confidence interval, we use t-distribution.b. With 98% confidence, the population mean number of days of class that the college student miss is between 3.921 and 8.479 days.c. If many groups of 15 randomly selected college students are surveyed, then a different confidence interval would be produced from each group. About 98% of these confidence intervals will contain the true population mean number of missed class days and 2% of these will not contain the true population mean number of missed class days.