Question

HELP ME PLS ASAP!!!!!!!!!!!

Answer 1

Answer:

$\sigma^2=73.96 \ kg^2$

Step-by-step explanation:

Standard Deviation and Variance

If we have a data set of measured values the variance is defined as the average of the squared differences that each value has from the mean. The formula to calculate the variance is:

$\displaystyle \sigma^2=\frac{\sum(x_i-\mu)^2}{n}$

Where $\mu$ is the mean of the measured values xi (i running from 1 to n), and n is the total number of values.

$\displaystyle \mu=\frac{\sum x_i}{n}$

The standard deviation is known by the symbol $\sigma$ and is the square root of the variance. We know the standar deviation of the weight in kg of a group of teenagers to be 8.6 kg. Thus, the variance is

$\sigma^2=8.6^2=73.96 \ kg^2$

$\boxed{\sigma^2=73.96 \ kg^2}$