The company pays a total of 10/100*$400000 = $<<10/100*400000=40000>>40000 on taxes
After taxes, the company revenue is $400000-$40000 = $<<400000-40000=360000>>360,000
The costs of marketing and ads campaign are 5/100*$360000 = $<<5/100*360000=18000>>18000
After deducting the costs of marketing and adds campaign, the company remains with = $342,000 in revenue
Operational costs for the company are 20/100*$342000 = $<<20/100*342000=68400>>68400
After taking out the operational costs, the company remains with $342000-$68400 = $273600
The company also pays employee wages of 15/100*$273600 =$<<15/100*273600=41040>>41040
If the total number of employees is 10, each employee is paid a salary of $41040/10 = $4104 per month
#### 4104