Answer:
[tex]Range = 11[/tex]
[tex]\sigma^2 = 12.1[/tex]
[tex]\sigma = 3.5[/tex]
Step-by-step explanation:
Given
[tex]Data: 16,12,17,8,15,15,10,11,19,18[/tex]
Solving (a): Range
This is calculated as:
[tex]Range = Highest - Least[/tex]
Where:
[tex]Highest = 19[/tex]
[tex]Least = 8[/tex]
So:
[tex]Range = 19 - 8[/tex]
[tex]Range = 11[/tex]
Solving (b): The population variance
First, calculate the population mean using:
[tex]\mu = \frac{\sum x}{n}[/tex]
So:
[tex]\mu = \frac{16+12+17+8+15+15+10+11+19+18}{10}[/tex]
[tex]\mu = \frac{141}{10}[/tex]
[tex]\mu = 14.1[/tex]
So, the population variance is:
[tex]\sigma^2 = \frac{\sum(x - \mu)^2}{n}[/tex]
[tex]\sigma^2 = \frac{(16 - 14.1)^2 + (12 - 14.1)^2 +............... + (19- 14.1)^2 + (18- 14.1)^2}{10}[/tex]
[tex]\sigma^2 = \frac{120.9}{10}[/tex]
[tex]\sigma^2 = 12.09[/tex]
[tex]\sigma^2 = 12.1[/tex] --- approximated
Solving (c): The population standard deviation.
This is calculated as:
[tex]\sigma = \sqrt{\sigma^2[/tex]
[tex]\sigma = \sqrt{12.09[/tex]
[tex]\sigma = 3.5[/tex]