SOLUTION: A distribution of measurements is relatively mound shape with a 70 and a standard deviation 10. What proportion of the measurements will fall between 60 and 80. What proportion of

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Question 748005: A distribution of measurements is relatively mound shape with a 70 and a standard deviation 10. What proportion of the measurements will fall between 60 and 80. What proportion of the measurement will fall between 50 and 90. What proportion of the measurement will fall between 50 and 80. If a measurement is chosen at random from this distribution what is the probability that it will be greater than 80.
Answer by stanbon(75887) About Me  (Show Source):
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A distribution of measurements is relatively mound shape with a 70 and a standard deviation 10. What proportion of the measurements will fall between 60 and 80.
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Using Chebyshev
What proportion of the measurement will fall between 50 and 90.
Each is 2 std away from the mean
The proportion is at least (1-(1/2)^2) = 0.75 = 75%
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What proportion of the measurement will fall between 50 and 80.
50 is 2 std below the mean so (1/2)0.75 = 37.5% is below the mean.
80 is 3 std above the mean so(1/2)0.95 = 47.5% is above the mean.
Ans: 0.375 + 0.475 = 85% is between 50 and 80
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If a measurement is chosen at random from this distribution what is the probability that it will be greater than 80.
Ans: 0.95 is between 50 and 80, so (1/2)0.05 = 0.025 is the answer
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Cheers,
Stan H.

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