Here's the math from "lolgfaqs" (by vegetaken)
Code:
You want the probability of it happening *at least* once.
Let's figure the *opposite* probability of it not happening at all.
If it happens 13% of the time, then it won't happen 87% of the time.
For it to *not* happen 3 times would be:
0.87 x 0.87 x 0.87 = 0.658503
Therefore the probability that it does happen at least once is 1 minus this:
1 - 0.658503
= 0.341497
Answer:
34% (not 39%)
Using the coins, if you were to toss a coin two times, you would have a 100% chance of getting at least one head. You can see that this logic is incorrect, because you could easily toss two tails. Additionally, if you tossed the coin *three* times you would have a 150% probability. :-D.
The correct probability of getting at least one head after 2 tosses is:
1 - 0.5 x 0.5
= 1 - 0.25
= 0.75
= 75%
The probability of getting at least one head after 3 tosses is:
1 - 0.5 x 0.5 x 0.5
= 1 - 0.125
= 0.875
= 87.5%
This number gets closer and closer to 100% with more tosses but won't ever reach it because there is always the *slight* possibility you get a string of tails on every toss.
Math is far from my forte, but Ferien the problem with your method is that you can have a probability/rate/whatever that exceeds 100% when we know that very little in DD mechanics in this game is 100%. If it does add up how you think it does, there'd have to be some kind of cap on crit rate.