SOLUTION: A final exam in MATH 121 has a mean of 73 with a standard deviation 7.80. If 34 students are randomly selected, find the probability that the mean of their test scores is less than
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Question 796325: A final exam in MATH 121 has a mean of 73 with a standard deviation 7.80. If 34 students are randomly selected, find the probability that the mean of their test scores is less than 76. Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website! A final exam in MATH 121 has a mean of 73 with a standard deviation 7.80. If 34 students are randomly selected, find the probability that the mean of their test scores is less than 76.
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z(76) = (76-73)/[7.8/sqrt(34)] = 2.2427
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P(x-bar < 76) = P(z < 2.2427) = normalcdf(-100,2.2427) = 0.9875
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Cheers,
Stan H.
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