Question

ms johnson uses a statistics program to analyze all the data collected by her students during a lab experiment about acceleration due to gravity. the program reports $overline{x} = 31.5$ and $sigma = 2.5$. what is the variance of the data? round to the nearest tenth. 1.6 2.5 5.6 6.3

Explanation:

Step1: Recall the formula for variance

Variance $\sigma^{2}$ is the square of the standard deviation $\sigma$.

Step2: Substitute the given value of standard deviation

Given $\sigma = 2.5$, then $\sigma^{2}=(2.5)^{2}$.
$$(2.5)^{2}=2.5\times2.5 = 6.25$$

Step3: Round to the nearest tenth

Rounding $6.25$ to the nearest tenth gives $6.3$.

Answer:

6.3