SOLUTION: The length of a screw produced by a machine is normally distributed with a mean of 0.75 inches and a standard deviation of 0.01 inches. What percent of screws are between 0.72 and
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Question 869645: The length of a screw produced by a machine is normally distributed with a mean of 0.75 inches and a standard deviation of 0.01 inches. What percent of screws are between 0.72 and 0.78 inches? Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website! The length of a screw produced by a machine is normally distributed with a mean of 0.75 inches and a standard deviation of 0.01 inches. What percent of screws are between 0.72 and 0.78 inches?
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z(0.72) = (0.72-0.75)/0.01 = -0.03/0.01 = -3
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z(0.78) = (0.78-0.75)/0.01 = 3
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P(-3< z <3) = normalcdf(-3,3) = 0.9973 = 99.73%
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Cheers,
Stan H.
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