Problem

Find the indicated IQ score. The graph to the right depicts IQ scores of adults, and those scores are normally distributed with a mean of 100 and a standard deviation of 15.
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The indicated IQ score, $x$, is ( Round to one decimal place as needed.)

Answer

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Answer

Therefore, the z-score for an IQ of 115 is \(\boxed{1.0}\). This means that an IQ of 115 is 1 standard deviation above the mean.

Steps

Step 1 :Given that the mean (μ) is 100, the standard deviation (σ) is 15, and the IQ score (x) is 115, we can calculate the z-score using the formula z = (x - μ) / σ.

Step 2 :Substitute the given values into the formula to get z = (115 - 100) / 15.

Step 3 :Simplify the expression to get z = 15 / 15.

Step 4 :Therefore, the z-score for an IQ of 115 is \(\boxed{1.0}\). This means that an IQ of 115 is 1 standard deviation above the mean.

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