Percentages

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A data set is normally distributed with the *mean* value $\mu = 69.00$ and *standard deviation* $\sigma = 15.00$. What percentage of data values are less than $x = 70.00$

**Answer**

*z-score* of $x=70.00 = z = \frac{x-\mu}{\sigma} = \frac{70.00 - 69.00}{15.00}=0.07$

The area under the *standard normal distribution curve* to the left of $z=0.07$ is $0.5279$

The percentage of data values that are less than $x=70.00$ is $52.79$