Question

A researcher has collected the following sample data. The variance and standard deviation values, respectively, are

5	12	6	8	5
6	7	5	12	4

Select one:

a. 0.907, 2.867

b. 2.867, 40.96

c. 8.222, 2.867

d. 2.867, 8.222

Answer 1

Solution:

x	x2
5	25
12	144
6	36
8	64
5	25
6	36
7	49
5	25
12	144
4	16
x=70	x2=564

Sample Variance S²

  S² =( x² ) - (( x)² / n ) n -1

=564-(70)²10 /9

=564-490/9

=74/9

=8.2222

Sample Variance =8.222

The sample standard is S

  S =( x² ) - (( x)² / n ) n -1

=564-(70)²10 /9

=564-490/9

=74/9

=8.2222

=2.8674

The sample standard =2.867

Option d) is correct.