posted by Asia on .
1.A magazine reported that 6% of Americans read the news paper while driving. 100 drivers are selected at random, find the probability that exactly 25 of them say they read the newspaper while driving.(normal binomial formula to solve)
2. A survey of 30 adults found that the mean age of a person's primary vehicle is 5.6 years. Assuming that the standard deviation of the population is 0.8 years find best point estimate of the population is 0.8 years find the best point estimate of the population mean and the 99% confidence interval of that population mean.
3.ten randomly selected people were asked how long they slept at night. The mean time was 7.1 hours and the (sample) standard deviation was 0.78 hours. Find the 95% confidence interval of the mean time. Assume the variable is normally distributed.