Question 848981: A manufacturer knows that their items have a normally distributed length, with a mean of 7.1 inches, and standard deviation of 1.7 inches.
Round your answer to four decimals.
If 24 items is chosen at random, what is the probability that their mean length is less than 6.2 inches?
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website! A manufacturer knows that their items have a normally distributed length, with a mean of 7.1 inches, and standard deviation of 1.7 inches.
Round your answer to four decimals.
If 24 items is chosen at random, what is the probability that their mean length is less than 6.2 inches?
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mean of the sample means:: 7.1 in
std of the sample means::: 1.7/sqrt(24)
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z(6.2) = (6.2-7.1)/[1.7/sqrt(24)] = -2.5936
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P(x-bar < 6.2) = P(z < -2.5936) = normalcdf(-100,-2.5936) = 0.0047
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Cheers,
Stan H.
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