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data collected for a study involving IQ scores of four year old girls produced a mean of 100 and a standard deviation of 10 what IQ score does a z-score of -1.5 represent

User LosManos
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6 votes

Answer:

85

Step-by-step explanation:

First, recall the formula for Z-Score.


Z-\text{Score}=(X-\mu)/(\sigma)\text{ where }\begin{cases}X=\text{raw score} \\ \mu=\operatorname{mean} \\ \sigma=\text{standard deviation}\end{cases}

Substitute the given values:


\begin{gathered} -1.5=(X-100)/(10)\text{ } \\ X-100=-1.5*10 \\ X-100=-15 \\ X=100-15 \\ X=85 \end{gathered}

A z-score of -1.5 represents ​an IQ score of 85.

User Jonas Berlin
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