Rota tool, criteria met.

[harbour1302]

Hi Guys,

I have an issue that i can't seem to get my head around.

I have a tool that i use to determine how many staff i require to open my restaurant. With the manager starting at 07:00.

The tool adds the following for each staff member starting;

07:00 = 1
08:00 = 0.75
09:00 = 0.5
10:00 = 0.25

The tool will give a time to complete opening prep without staff so for example 7 Hours to complete.
We open at 11:00 so the tool takes into consideration the manager starting time then once you manually add the staff starting times it will divide the total hours needed by the staff decimal totals.
For example 8 hours to complete prep with manager at 7:00 divided by 1.75 will give 4 hours and 57 minutes added to the manager starting time of 7:00 would give 11:57.

What i need is a formula that will automatically tell me the required staff based on the decimal value of staff starting time until the desired criteria of 11:00 is met.
So once i add the hours needed, the formula would automatically run through the potential starting times and tell me exactly who i would need to start and at what times to finish closest to 11:00.

Is this possible and i hope it makes sense.

Thanks