How To Allocate Percentages Of A Number Across Different Fields

We have a model at my job which shows every job code one can do (there are only about 25 of these jobs) For example, let's say one job is called "Trade Settlements" and it's been estimated that we spend about 1000 minutes a day doing this particular job across the entire floor.

Well, I want to come up with a way to allocate the minutes of this to certain hour blocks and determining whether our group is over/understaff given the results.

So let's say I want, 30% of it to be done from 9-10 am, 10% done over the next 4 hour time blocks, and 2-3 pm for the remaining 30%.

Thus, we'd get something something like 300, 100, 100, 100, 100, 300 minutes and 0's for other time blocks.

These percentages would be input fields so if anyone types in a percentage, they get # of minutes spent for that hour on that job. Ultimately we would add these numbers up with other jobs and be able to easily update from there for any job type we wanted.