Question

The monthly earnings of computer systems analysts are normally distributed with a mean of $4,300. If only 1.07% of the systems analysts have a monthly income of more than $6,140, what is the value of the standard deviation of the monthly earnings of the computer systems analysts?

Answer 1

Answer:800

Step-by-step explanation:

$Mean(\mu )=\ 4300$

and $P(X>6140)=0.0107$

$P(X>x_0)=0.0107$

$P\left ( \frac{X-\mu }{\sigma}<\frac{x-\mu }{\sigma} \right )=0.9893$

$P\left ( z<\frac{x-\mu }{\sigma} \right )=0.9893$

$\frac{x-\mu }{\sigma}=InvNormal(0.9893)$

Using Z table to get InvNormal(0.9893)=2.30

$\frac{6140-4300}{\sigma}=2.30$

$\sigma =\frac{6140-4300}{2.30}=800$

Answer 2

Answer:

800

Step-by-step explanation: