Although controversial, some human resources departments administer standard IQ tests to

potential employees. The Stanford-Binet test scores are well modelled by a Normal model with mean 100 and standard deviation 19. If the applicant pool is well modelled by this distribution, a randomly selected applicant would have what probability of scoring in the following regions? Use the 68-95-99.7 Rule to approximate the probabilities rather than using technology to find the values more precisely.

a) What is the probability of scoring 100 or above?

(Type an integer or a decimal.)

A survey of 200 middle managers showed a distribution of the number of hours of exercise they participated in per week with a mean of 3.77 hours and a standard deviation of 4.92

hours.

a) According to the Normal model, what percent of managers will exercise fewer than one standard deviation below the mean number of hours? (Round to the nearest whole number as needed.)

A tire manufacturer believes that the tread life of its snow tires can be described by a Normal model with a mean of 30,000 miles and a standard deviation of 2300

miles.

a) If you buy a set of these tires, would it be reasonable for you to hope that they'll last

36,000 miles?

About (enter your response here%) of tires are expected to have a tread life greater than

36,000 miles. It (would not OR would) be reasonable to hope that your tires lasted this long.

(Round to one decimal place as needed.)

In an effort to check the quality of their cell phones, a manufacturing manager decides to take a random sample of 10 cell phones from yesterday's production run, which produced cell phones with serial numbers ranging (according to when they were produced) from 43005000 to 43005999. The manager noticed that the number of faulty cell phones in the production run of cell phones is usually small and that the quality of one day's run seems to have no bearing on the next day.

b) If the mean number of faulty cell phones is 2.7 per day, what is the probability that no faulty cell phones will be produced tomorrow? (Round to four decimal places as needed.)