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Author Topic: Math question about probability / adding probabilities together  (Read 554 times)

daniellogin

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Math question about probability / adding probabilities together
« on: September 23, 2019, 03:05:52 AM »
Example:

Round 1 you have a 3/4 chance to pick the right choice. So far it's easy, it's 75% probability to win. But what happens when round 2 has you pick from 4 choices again, with 3 again being the win? Is it overall still 1/4 chance to win?

If not, maybe it's something like you get the 3 (out of 4) from the first, then say 75% of that, which is 2.25... which is 56% of 4?

Anyone know how to do math? I just pretend I do...

djaydino

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Re: Math question about probability / adding probabilities together
« Reply #1 on: September 23, 2019, 05:58:30 AM »
Hi.
Its 56.25‬% IF only 2 rounds
to get to this data, first get the total possibilities (16)
Then count wrong or right for each possibilities (9 right / 7 wrong)

then do 9 (right) divide by 16
This will give the normalized % 0.5625 * 100 = 56.25%


daniellogin

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Re: Math question about probability / adding probabilities together
« Reply #2 on: September 23, 2019, 06:18:44 AM »
Thanks.

This come up because I'm making a mini game where it's just going to be probability (no skill or method), but made a little bit more interesting along the way. The idea is the player will go through several chambers of multiple choices where they will either die (a different comical way) or progress to the last chamber to win.

I want it to be more likely that the player will win rather than lose, so realised I have to do the math to make sure.

Thore

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Re: Math question about probability / adding probabilities together
« Reply #3 on: September 23, 2019, 04:33:23 PM »
When several probabilities need to occur for an outcome, you need to multiply them: 0.75 * 0.75 = 0.56 = 56%

djaydino

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Re: Math question about probability / adding probabilities together
« Reply #4 on: September 24, 2019, 06:18:17 AM »
Hi.
Ah yes That's a way better way to do this Thanks Thore
i actually used this already in one of my gambling games a long time ago, but forgot they way i did :D

You can even combine Several round with different chances for example if round 1 would be 0.75 (75) and round 2 would be 0.5 (50%)
Result 0.375 (37.5%) if you have a 3rd leveldo the result Multiplied by the change on that level.
So if on that level would be 75% do 0.375 * 0.75 = 0.28125 (28.125%)

Thore

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Re: Math question about probability / adding probabilities together
« Reply #5 on: September 25, 2019, 06:10:44 AM »
Hi, I had to double check as well. :) Your explanation is still correct why this works.