Question 629237
In a particular region of Cape Cod, it is known that lobstermen trap on average of 32 pounds of lobster per day with a standard deviation of four pounds. If a random sample of 30 lobster fishermen is selected, what is the probability that their average catch is less than 31.5 pounds?
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z(31.5) = (31.5-32)/[4/sqrt(30)] = -0.6847
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P(x-bar < 31.5) = P(z < -0.6847) = normalcdf(-100,-0.6847) = 0.2468
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Note: If you use a t-distribution you will get a slightly different
answer.
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Cheers,
Stan H.
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