## Prob. of >= 1 successes, exactly k successes in n trails?

Standard deviation, mean, variance, z-scores, t-tests, etc.
zorro
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### Prob. of >= 1 successes, exactly k successes in n trails?

Question : An infinite sequence of independent trails is to be performed . Each trail results in a success with the probability p and a failure 1-p . What is the probability that
i) at least 1 success occurs in the first n trails
ii) exactly k success occur in the first n trails
iii) all trails result in successes

Note : please provide only the end result ....Need to verify if its correct or no ?

maggiemagnet
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### Re: Prob. of >= 1 successes, exactly k successes in n trails

please provide only the end result ....Need to verify if its correct or no ?

jk22
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Joined: Sat Jun 26, 2010 10:39 am
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### Re: Prob. of >= 1 successes, exactly k successes in n trails

Hi, nice to meet you.
did you get :
i) 1-(1-p)^n
ii) p^k(1-p)^(n-k)
iii)p^n->0 as n tends to infty ?

cya.