Question 758340: The breaking strength (in pounds) of a certain new synthetic is normally distributed, with a mean of 135 and a variance of 4. The material is considered defective if the breaking strength is less than 131 pounds. What is the probability that a single, randomly selected piece of material will be defective?
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website! The breaking strength (in pounds) of a certain new synthetic is normally distributed, with a mean of 135 and a variance of 4. The material is considered defective if the breaking strength is less than 131 pounds. What is the probability that a single, randomly selected piece of material will be defective?
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z(131) = (131-135)/4 = -4/4 = -1
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P(x < 131) = P(z < -1) = normalcdf(-100,-1) = 0.1587
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Cheers,
Stan H.
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