Question

Given he population of numbers 3,6,8,9 and 4. Suppose samples of size 3 are drawn from this population .

1. What is the mean and the variance of the population?

Answer 1

$EX=\frac{3+6+8+9+4}{5}=6\\DX=\frac{\left( 3-6 \right) ^2+\left( 6-6 \right) ^2+\left( 8-6 \right) ^2+\left( 9-6 \right) ^2+\left( 4-6 \right) ^2}{5}=5.2$