All of the following refer to bolts with a mean length of 5.0 inches and standard deviation
Question:
All of the following refer to bolts with a mean length of 5.0 inches and standard deviation of 0.1 inches. Note: The standard deviation throughout this problem is 1/10 of an inch, not one inch.
A) Your firm manufacturers bolts for use in tractors. Your firm guarantees that the length of the bolts is at least 4.85 inches long. What percentage of the time will your firm have to pay off on this guarantee because the length of the bolts is smaller than 4.85 inches?
B) Your firm guarantees that the length of the bolts is no more than 5.25 inches long. What percentage of the time will your firm have to pay off on this guarantee because the length of the bolts is greater than 5.25 inches?
C) Your firm wants to guarantee that the length of the bolts is no more than a certain length, and the firm does not want to have to pay off on the guarantee more than 5% of the time. The firm should say that they guarantee bolts will not be longer than what length? Format your answer with four digits after the decimal point.
D) Your firm guarantees that no more than 5% of the bolts will be defective (too long or too short). What upper and lower limits (lengths) for the bolts should the firm guarantee? Format your answer with four digits after the decimal point.