14. A machine can be adjusted so that when under control, the mean amount of powdered soap filled in a bag is 5 kilos. From past experience, the standard deviation of the amount filled is known to be 0.15 kilos. To check if the machine is under control, a random sampleof sixteen bags was weighed and the mean weight was found to be 5.1 kilos. At 1% significance level, is the adjustment our of control? (Assume a normal distribution of the amount of powered soap filled in a bag.)
15. A paint manufacturing company claims that the mean drying time for its paints is 45minutes. A random sample of 35 gallons of paints 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 time for these paints have a normal distribution. Using 1% significance level, would you conclude that the company’s claim is true?
Already registered? Login
Not Account? Sign up
Enter your email address to reset your password
Back to Login? Click here