Unit sales for new product ABC have varied in the first seven months of this year as follows: Month Jan Feb Mar Apr May Jun Jul Unit Sales 148 329 491 167 228 285 441 What is the (population) standard deviation of the data

Respuesta :

Answer:

[tex]\sigma = 121.53[/tex]

Step-by-step explanation:

Required

The population standard deviation

First, calculate the population mean

[tex]\mu = \frac{\sum x}{n}[/tex]

This gives:

[tex]\mu = \frac{148+ 329+ 491 +167+ 228+285+ 441}{7}[/tex]

[tex]\mu = \frac{2089}{7}[/tex]

[tex]\mu = 298.43[/tex]

The population standard deviation is:

[tex]\sigma = \sqrt{\frac{\sum(x - \bar x)^2}{n}}[/tex]

So, we have:

[tex]\sigma = \sqrt{\frac{(148 - 298.43)^2 + ..........+ (441- 298.43)^2}{7}}[/tex]

[tex]\sigma = \sqrt{\frac{103387.7143}{7}}[/tex]

[tex]\sigma = \sqrt{14769.6734714}[/tex]

[tex]\sigma = 121.53[/tex]