Answer to Question #345206 in Statistics and Probability for Shy

Question

A group of students got the following scores in a test: 6, 9, 12, 15, 18, and 21. Consider samples of size 3 that can be drawn from this population

Answer 1

There are a total of 20 combinations

The samples are

6,9,12

$Mean =\frac{6+9+12}{3} = 9$

6,9,15

$Mean =\frac{6+9+15}{3} = 10$

6,9,18

$Mean =\frac{6+9+18}{3} = 11$

6,9,21

$Mean =\frac{6+9+21}{3} = 12$

6,12,15

$Mean =\frac{6+12+15}{3} = 11$

6,12,18

$Mean =\frac{6+12+18}{3} = 12$

6,12,21

$Mean =\frac{6+12+21}{3} = 13$

6,15,18

$Mean =\frac{6+15+18}{3} = 13$

6,15,21

$Mean =\frac{6+15+21}{3} = 14$

6,18,21

$Mean =\frac{6+18+21}{3} = 15$

9,12,15

$Mean =\frac{9+12+15}{3} = 12$

9,12,18

$Mean =\frac{9+12+18}{3} = 13$

9,12,21

$Mean =\frac{9+12+21}{3} = 14$

9,15,18

$Mean =\frac{9+15+18}{3} = 14$

9,15,21

$Mean =\frac{9+15+21}{3} = 15$

9,18,21

$Mean =\frac{9+18+21}{3} = 16$

12,15,18

$Mean =\frac{12+15+18}{3} = 15$

12,15,21

$Mean =\frac{12+15+21}{3} = 16$

12,18,21

$Mean =\frac{12+18+21}{3} = 17$

15,18,21

$Mean =\frac{15+18+21}{3} = 18$