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Probability of Sample Mean

Jim Sears manufactures farm equipment. His work requires the use of steel bars which must have a mean length of at least 50 inches. The bars can be purchased from a supplier in Kansas City whose bars average only 47 inches with a standard deviation of 12 inches, or from a supplier in Dallas whose bars average 49 inches with a standard deviation of 3.6 inches.

If Sears is to buy 81 bars from Kansas City, what is the probability they will have a mean of at least 50 inches? (Show calculations)

If Sears is to buy 81 bars from Dallas, what is the probability they will have a mean of at least 50 inches? (Show your calculations)

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Jim Sears manufactures farm equipment. His work requires the use of steel bars which must have a mean length of at least 50 inches. The bars can be purchased from a supplier in Kansas City whose bars average only 47 inches with a standard deviation of 12 inches, or from a supplier in Dallas whose bars average 49 inches with a standard deviation of 3.6 inches.

If Sears is to buy 81 bars from Kansas City, what is the probability they will have a mean of at least 50 inches? ...

Solution Summary

Calculates probability of sample mean.

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