SOLUTION: I really don't know the steps to take to get this answer. Could you please show me a step by step? The mean IQ score for 1500 students is 100, with the standard deviation of 15.

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Question 465043: I really don't know the steps to take to get this answer. Could you please show me a step by step?
The mean IQ score for 1500 students is 100, with the standard deviation of 15. Assuming the scores have a normal curve, how many have an IQ between 85 and 115?
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
I really don't know the steps to take to get this answer. Could you please show me a step by step?
The mean IQ score for 1500 students is 100, with the standard deviation of 15. Assuming the scores have a normal curve, how many have an IQ between 85 and 115?
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z(115) = (115-100)/15 = 1
z(85) = (85-100)/15 = -1
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P(85< x < 115) = P(-1< z < 1) = 0.6827
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# of 1500 that have IQ between 85 and 115 = 0.6827*1500 ~ 1024
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Cheers,
Stan H.
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