For the numerical questions below, express your answers in four decimal places.
Past experience indicates that monthly data use from mobiles is normally distributed with a mean of 399 MB and a population standard deviation of 359 MB. After an advertising campaign aimed at showcasing the new nationwide 4G network, the manager of a telecommunications firm took a random sample of 23 customers and recorded their monthly data usage. The manager found the sample average to be 451.4 MB. The manager is looking to conduct a statistical test at the 10% level of significance to determine whether the campaign has changed customers downloading habits.
Part A) What is the null hypothesis?
H0: ? = 399
H0: ? ? 399
H0: ? > 451.4
H0: ? = 451.4
H0: X?= 399
Part B) What is the alternate hypothesis?
H1: ? ? 399H1: ? = 399H1: ? ? 451.4H0: ? ? 451.4H0: X?? 399
Part C) What is the value of ??
Part D) What is the sampling distribution of the sample mean?
The sampling distribution is normal since the population standard deviation is known.The sampling distribution is a student-t since the population standard deviation is known.There is not enough information to answer this question.
Part E) What is the value of the test statistic?
Part F) What is the p-value?