<PRE><B>Question 909684</B>
Suppose standard IQ scores are known to be normally distributed with mean of 100 and standard deviation of 15. Find the probability that a randomly selected individual with IQ score between 90 and 120.
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z(90) = (90-100)/15 = -2/3
z(120) = (120-100)/15 = 4/3
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P(90&lt; x &lt;120) = P(-2/3 &lt; z &lt; 4/3) = normalcdf(-2/3,4/3) = 0.6563
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Cheers,
Stan H.
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