SOLUTION: According to R.L. Polk & Co., the average age of cars and light trucks in the U.S. in 2011 was 10.8 years. Assume the standard deviation for this population is 3.7 years. A sample
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-> SOLUTION: According to R.L. Polk & Co., the average age of cars and light trucks in the U.S. in 2011 was 10.8 years. Assume the standard deviation for this population is 3.7 years. A sample
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Question 886214: According to R.L. Polk & Co., the average age of cars and light trucks in the U.S. in 2011 was 10.8 years. Assume the standard deviation for this population is 3.7 years. A sample of 35 randomly selected vehicles was selected. What is the probability that the sample mean will be greater than 10 years?
A. 0.5469
B. 0.7812
C. 0.8997
D. 0.9846
You can put this solution on YOUR website! According to R.L. Polk & Co., the average age of cars and light trucks in the U.S. in 2011 was 10.8 years. Assume the standard deviation for this population is 3.7 years. A sample of 35 randomly selected vehicles was selected. What is the probability that the sample mean will be greater than 10 years?
z(10) = (10-10.8)/(3.7/sqrt(35)) = -0.0365
P(x-bar > 10) = P(z > -0.0365) = normalcdf(-0.0365,100) = 0.5146
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Cheers,
Stan H.
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A. 0.5469
B. 0.7812
C. 0.8997
D. 0.9846
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