Statistician 7500

A statistician monitored the variance of monthly wages and found its value to be 640,000. Determine the standard deviation of salaries if there is a one-off increase:
a) about CZK 1,800,
b) about 5%.

Correct answer:

a =  800
b =  840

Step-by-step explanation:

$$\begin{gathered} r=640000 \\ a=\sqrt{r}=\sqrt{640000}=800 \end{gathered}$$

$b=a\cdot 1.05=800\cdot 1.05=840$

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