There are a total of 3326 items, you can call them balls, of various colours. 171 of them are blue. You can either consider this as drawing one ball at a time or a handfull of 50 balls (just imagine you have a giant's hand). What is the probability that at least one of the first 50 balls will be blue?
This isn't for homework or anything, I was just trying to figure out the probability of this x event happening and I thought it would be some quick math but I've been at it for a few days now so I'm quite obsessed at this point. Been asking around and no one can solve this properly. I even tried to make a program in python to speed up calculations but I'm failing at the logic of approaching this problem I think, so the results are all wrong. I got 2.58% using one method, 5.18 using another, 93% using python...
I looked at is as permutation, so used formula [MATH]\frac{n!}{((n-k!)*k!)}[/MATH]where
n = total number of outcomes (3326)
k = favourable outcomes (171)
But no calculator can do 3326! so... got stuck
I tried looking at it as each draw is an event, and the formula for that being P(a or b) = P(a) + P(b) - P(a and b)
and P(a and b) = P(a) x P(b)
So I applied it to my problem, replacing a and b with each draw, so there will be 50 events:
P(e1 or e2 or e3 ... or e50) = P(e1) + P(e2) ... + P(e50) - (Pe1 and e2 ... and e50)
Just to clarify, I took each event to mean the probability of drawing a blue ball on first draw, second draw, third draw etc. So first draw would be [MATH]\frac{171}{3326}[/MATH], second draw would be [MATH]\frac{171}{3325}[/MATH], third draw [MATH]\frac{171}{3324}[/MATH] etc.
This is a situation of choosing without replacement.
After a loooong time calculating each event's probability and adding/multiplying them, I got the 2.58 which I assumed it represented percentage. I don't know if I got it right. Feels like it's too high maybe.
Can someone just tell me the answer but also what was the right way to calculate it?
This isn't for homework or anything, I was just trying to figure out the probability of this x event happening and I thought it would be some quick math but I've been at it for a few days now so I'm quite obsessed at this point. Been asking around and no one can solve this properly. I even tried to make a program in python to speed up calculations but I'm failing at the logic of approaching this problem I think, so the results are all wrong. I got 2.58% using one method, 5.18 using another, 93% using python...
I looked at is as permutation, so used formula [MATH]\frac{n!}{((n-k!)*k!)}[/MATH]where
n = total number of outcomes (3326)
k = favourable outcomes (171)
But no calculator can do 3326! so... got stuck
I tried looking at it as each draw is an event, and the formula for that being P(a or b) = P(a) + P(b) - P(a and b)
and P(a and b) = P(a) x P(b)
So I applied it to my problem, replacing a and b with each draw, so there will be 50 events:
P(e1 or e2 or e3 ... or e50) = P(e1) + P(e2) ... + P(e50) - (Pe1 and e2 ... and e50)
Just to clarify, I took each event to mean the probability of drawing a blue ball on first draw, second draw, third draw etc. So first draw would be [MATH]\frac{171}{3326}[/MATH], second draw would be [MATH]\frac{171}{3325}[/MATH], third draw [MATH]\frac{171}{3324}[/MATH] etc.
This is a situation of choosing without replacement.
After a loooong time calculating each event's probability and adding/multiplying them, I got the 2.58 which I assumed it represented percentage. I don't know if I got it right. Feels like it's too high maybe.
Can someone just tell me the answer but also what was the right way to calculate it?
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