Help: House Bill Computation (Divider)

So, i'm planning to make an excel sheet to divide a House Electricity Bill among the users.

Here's the Situation:
- This is for the Electric Bill distribution among 15 people who live in the same house.
- The bill has to be divided among all and also on how many days they have stayed and used the service.

Please see the attached sheet to have more idea on what i'm trying to achieve.

Help.