I would like to know the formula that would allow me to do the following;

Assume;

1. 200 total events occur in 100 days (ie; 2 events per day)

2. Total events sum is made up where a = 60, b = 100 and c = 40.

For each day, I want to know (the probability) of the event was from which combination of a, b, or c based upon their percentages to the whole (200).

Thanks