to be fair
If you used one bottle of baby oil a day for twenty years, you would calculate the total number of bottles as follows:
Determine the number of days in twenty years:
20 years × 365 days/year = 7,300 days
(Note: This does not account for leap years. If you want to include leap years, you would add about 5 extra days for the 5 leap years in that period, making it approximately 7,305 days.)
Since you are using one bottle per day, the total number of bottles would be:
7,300 bottles (or approximately 7,305 if accounting for leap years).
So, you would use about 7,300 to 7,305 bottles of baby oil over twenty years.