Based on the 1990 census, the number of hours per day adults spend watching television is approximately normally distributed with a mean of 5 hours and a standard deviation of 1.3 hours.
- What proportion of the population spends more than 7 hours per day watching television?
- In a 1998 study of television viewing, a random sample of 500 adults reported that the average number of hours spent viewing television was greater than 5.5 hours per day. Do the results of this survey appear to be consistent with the 1990 census? (Hint: If the census results are still correct, what is the probability that the average viewing time would exceed 5.5 hours?)