Division R of Company Q has 1,000 employees. What is the average (arit

cant we just add both averages together and then divide over 2? i know it´s a stupid question but pls guys be so kind and tell me logically why not

thank you

No. That cannot be done. Check the following.

if total employees of division A is x1 and total salary is s1 then average = s1/x1.
If rest of employees is x2 and total salary of these is s2 then average = s2/x2.

Sum of the two averages = (s1/x1) + (s2/x2).

However, average at the company level = (s1+s2)/(x1+x2) and this is not the same as (s1/x1) + (s2/x2).

I hope, this helps.

We can express the average annual salary of Company Q as:

\(S = \frac{S_r * N_r+ S_{not-r}*N_{not-r}}{N_r+N_{not-r}}\)

where
- \(S_r\) - The average annual salary of the employees in Division R
- \(S_{not-r}\) - The average annual salary of the employees who are not in Division R
- \(N_r\) - The number of employees in Division R
- \(N_{not-r}\) - The number of employees who are not in Division R

So, we don't know the number of employees who are not in Division R.

You can also use huge/tiny numbers to check your answer. If \(N_{not-r}=0\) or only 1 employee, S = 30K or will be very close to 30K. At the same time, if \(N_{not-r}>>1000\), S will be very close to 35K. So we need to know at least \(\frac{N_{not-r}}{N_r}\) ratio.

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