Stats Final guide Essay

2992 WordsMar 21, 201412 Pages
STATISTIC (1) A study of the number of cars sold looked at the number of cars sold at 500 Dealers The smallest dealer had 11 cars sold and the largest had 154 cars sold. If you were going to create a frequency distribution of the number of cars sold using six classes in your frequency distribution, which of the following might be a reasonable first class? (a) 0 to 25 _ (2) Give that a sample of 25 had x = 75, and (x-x)² = 48 the mean and standard deviation are _ (c)…show more content…
(a) Choose a probability for your type ll error. (e) None of the above. (20) An urban planner wished to determine whether there is sufficient evidence to conclude that the mean family income in the San Fernando Valley exceeds $38000. When the urban planner collects data on family incomes, he would – (a) Use a one-tailed test with the alternative to the right (above $38000) (21) You took a sample of size 21 from a normal distribution with a known standard deviation, . In order to find a 90% confidence interval for the mean, You need to find. (a) Then mean of the sample and the value of Z with an area of 10% in right tail. (b) The value of Z with an area of 5% in the right tail, but not the sample mean. (c) The mean of the sample and the value of Z with an area of 5% in the left tail. (d) More information than given by any of a, b, or c. (22) A study was conducted in Malibu on the value of a house (Y, in thousands of dollars) as it relates to the distance the house is from the beach (X, in miles). The result was the regression equation, Y= 800-20X. In the equation, the number 20 represents. (c) For each extra mile a house is from the
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