I know about those expressions but what I wasn't concerned about the dice roll but the drop chance every object has. I also want the decimals for comparing.
I already read your post but in concept, they work just the same you just added a step before to see which bag of items had every enemy which is one of the many ways for dropping items.
but let's say I want to drop equipment from your example:
-I have 100/6 chances to get an owl
-from that 100/6 I have a 15% chance to drop something
-That chance is then divided equally between the number of objects on the bag (rarity=bag)
-so 15%/6 chances to drop equipment per roll
If I'm not wrong (I suck at math so probably) equipment has a 0,41% chances to drop.
If I want to add a 25% chances to drop to the equipment it's not as easy as adding 25 to its rarity It just makes it drop on more enemies, but that's not what I want.
Think of it as If you opening a pack on a game of cards: common(52%), rare(44%), epic(4%).
and I want to add a 20% boost to rare chances because of an item or skill.
else roll<=(obj1_drop_rate + obj2_drop_rate)
else roll<=(obj1_drop_rate + obj2_drop_rate)+ obj3_drop_rate
That's what the math on the first post was for, substracting drop chance from the other objects depending on their drop chance.
I don't need to make tables for that, and I can certainly just do it as I've been doing it until now I was just curious about if there are better ways to do it.
I probably can't explain myself properly sorry.