Round each z-score to the nearest hundredth. A data set has a mean of x = 6.8 and a standard deviation of 2.5. Find the z-score. x=7.2

Round each z-score to the nearest hundredth. A data set has a mean of x = 6.8 and a standard deviation of 2.5. Find the z-score. x=7.2

Question
Random variables
asked 2021-02-25
Round each z-score to the nearest hundredth.
A data set has a mean of
\(\displaystyle{x}={6.8}\)
and a standard deviation of 2.5. Find the z-score.
\(\displaystyle{x}={7.2}\)

Answers (1)

2021-02-26
Obtain the Z-score for the random variable X value equals 7.2.
The Z-score for the random variable X value equals 7.2 is obtained below as follows:
Let X denote the random variable with the population mean 7.2 and the standard deviation of 2.5.
The required value is,
\(\displaystyle{Z}={\frac{{{X}-\mu}}{{\sigma}}}\)
\(\displaystyle={\frac{{{7.2}-{6.8}}}{{{2.5}}}}\)
\(\displaystyle={\frac{{{0.4}}}{{{2.5}}}}=-{0.16}\)
The Z-score for the random variable X value equals 7.2 is 0.16.
0

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