I have been trying to figure this out, have done many, many searches, read hundreds of pages, and still cannot understand the calculation. (Most questions have to do with lotto odds... )

The specifics are, for example:

100,000 entries
5 prizes of equal value
50 entries.

I thank anyone for assistance, and would learn quite a bit in the process. I have been fine understanding the process until the 5 equal prizes come into play, and how they affect the numbers.