Consider two populations of students. Both populations are the same size (1000). The first population consists of all students at a grade school (grades 1-5). The second population consists of all students at a middle school (grades 6-8). Which school's population is more likely to have a larger standard deviation in the age of its students? a) The grade school's population is more likely to have the larger standard deviation. b) The middle school's population is more likely to have the larger standard deviation. c) They would most likely have the same standard deviation for age. a) It is impossible to say without more information.

1- Computer Literacy Test If 80% of job applicants are able to pass a computer literacy test, find the mean, variance, and standard deviation of the number of people who pass the examination in a sample of 150 applicants. 2- Fuel Efficiency for U.S. Light Vehicles The average fuel efficiency of U.S. light vehicles (cars, SUVS, minivans, vans, and light trucks) for 2005 was 21 mpg. If the standard deviation of the population was 2.9 and the gas ratings were normally distributed, what is the probability that the mean mpg for a random sample of 25 light vehicles is under 20? Between 20 and 25? 3- Elementary School Teachers Women comprise 80.3% of all elementary school teachers. In a random sample of 300 elementary chers, what is the probability that less than three-fourths are women?

Five students took a self-confidence test. Their deviation scores were –4, +3, +1, –2, and +2. Assuming that these scores com form a normaldistribution, which deviation represents the highest raw score?

Airfares Each year a company must send 3 officials to ameeting in China and 5 officials to a meeting in France. Airline ticket prices vary from time to time, but the com-pany purchases all tickets for a country at the same price. Past experience has shown that tickets to China have amean price of $1000, with a standard deviation of $150,while the mean airfare to France is $500, with a standarddeviation of $100.a) Define random variables and use them to express thetotal amount the company will have to spend to sendthese delegations to the two meetings.b) Find the mean and standard deviation of this total cost. c) Find the mean and standard deviation of the dif-ference in price of a ticket to China and a ticket to France.d) Do you need to make any assumptions in calculatingthese means? How about the standard deviations?