I am trying to take a number, use it to calculate so many hours and minutes, then subtract this from an end time to give me a start time for A11 below:

A1 - number of pounds a turkey weighs

A11 – some formula that takes the number in A1, does a calculation based on 10 minutes per pound then subtracts this time from A33 to give me a start time. For example, 18 pound would be 3 hours that would be subtracted from 5:00 PM to give me 2:00 PM

A33 – time, e.g., 5:00 PM