The amount that households pay service providers for access to the Internet varies quite a bit, but the mean monthly fee is $50 and the standard deviation is $20. The distribution is not Normal: many house- holds pay a low rate as part of a bundle with phone or television service, but some pay much more for Inter- net only or for faster connections. A sample survey asks an SRS of 50 households with Internet access how much they pay. Let x be the mean amount paid.
(a) Explain why you can't determine the probability that the amount a randomly selected household pays for access to the Internet exceeds $55.
(b) What are the mean and standard deviation of the sampling distribution of ?
(c) What is the shape of the sampling distribution of x? Justify your answer.
(d) Find the probability that the average fee paid by the sample of households exceeds $55. television service, but some pay much more for Inter- net only or for faster connections.