Standard Deviation: Videos & Practice Problems

A population includes the values $\text{4}$ hours, $7$ hours, and $15$ hours of study time per week, based on a student survey. Randomly select samples of two values with replacement from this population and list all possible pairs.
Calculate the sample variance, $s^2$, for each sample using the formula that divides by $n-1$. Finally, determine the average of all computed sample variances.