The amount of fuel used by jumbo jets to take off is normally distributed with a mean of 4,000 gallons and a standard deviation of 125 gallons. A sample of 40 jumbo jets is randomly selected. (No need to interpolate) a. Compute the z-score for 3, 950 gallons. b. What is the probability that the mean number of gallons of fuel needed to take off for a randomly selected sample of 40 jumbo jets will be less than 3, 950 gallons? c. What is the probability that the mean number of gallons of fuel needed to take off for a randomly selected sample of 40 jumbo jets will be more than 3, 950 gallons?

The scores of individual students on the American College Testing (ACT), a college readiness assessment, have a Normal distribution with a mean of 18.6 and a standard deviation of 6.0. At Northside High, 36 seniors take the test. Assume the scores at this school have the same distribution as national scores. What is the mean of the sampling distribution of the sample mean score for a random sample of 36 students? 0 1 0 6

Refer to the accompanying table, which describes results from groups of 8 births from 8 different sets of parents. The random variable x represents the number of girls among 8 children. Find the mean and standard deviation for the number of girls in 8 births. Click the icon to view the data table. The mean is u= girl(s). (Round to one decimal place as needed.) The standard deviation is o = e# girl(s). (Round to one decimal place as needed.) Table of numbers of girls and probabilities Number of Girls x 0 1 2 3 4 5 6 7 8 átv P(x) 0.004 0.034 0.117 0.218 0.278 0.217 0.102 0.027 0.003 D - X NiZ Next

Refer to the accompanying table, which describes results from groups of 8 births from 8 different sets of parents. The random variable x represents the number of girls among 8 children. Find the mean and standard deviation for the number of girls in 8 births. Click the icon to view the data table. The mean is u = girl(s). (Round to one decimal place as needed.) The standard deviation is o = girl(s). (Round to one decimal place as needed.)