SOLUTION: A paint manufacturing company claims that the mean drying time for its paint is not more than 45 minutes. A random sample of 20 gallons of pain selected from the production line of
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Question 872076: A paint manufacturing company claims that the mean drying time for its paint is not more than 45 minutes. A random sample of 20 gallons of pain selected from the production line of this company showed that the mean drying time for this sample is 50 minutes with a standard deviation of 3 minutes. Assume that the drying times for these paints have a normal distribution
Using the significance level would you conclude that the company's claim is true?
Thank you for taking the time and for your help!!! Answer by ewatrrr(24785) (Show Source):
You can put this solution on YOUR website! Ho: u ≤ 45 (claim)
Ha: u > 45
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Sample of 20: Sample mean = 50, Sample SD = 3
t(50) = (50-45)/(3/sqrt(20)) = 5/.67= 7.46
P(t > 7.46 when df = 19) = basically 0
0 < .05 This is a 95% confidence Interval
reject manufacturer's claim at any confidence Interval
