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16 Aug 2006, 03:41
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a question - a lot of the probability questions, esp. Coin tosses etc. are solved by mapping out "HHH TTT HHT TTH" etc. [heads = H, Tails = T].
Is there a quicker way of doing such problems?
_________________
Saumil Annegiri,
Business Analyst (Philly, PA)
Is there a quicker way of doing such problems?
_________________
Saumil Annegiri,
Business Analyst (Philly, PA)
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16 Aug 2006, 03:45
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Remember for independent trials in which the probability of success in any given trial is p, the probability of getting exactly k successes in n trials is
nCk*p^k*(1-p)^(n-k) where nCk= n!/((n-k)!*k!)
Examples:
(A) What's the probability that, upon rolling a fair dice 6 times, exactly 3 1's are obtained?
(B) What's the probability that, upon tossing a fair coin 100 times, 17 heads are obtained?
(C) If the probability that it snows in any given year in San Francisco is 0.1, what is the probability that it will snow in 8 of the ten years of the 2010's?
(A) 6C3* 5^3/6^3
(B) (100C17)/2^100
(C) (10C8)/10^8
nCk*p^k*(1-p)^(n-k) where nCk= n!/((n-k)!*k!)
Examples:
(A) What's the probability that, upon rolling a fair dice 6 times, exactly 3 1's are obtained?
(B) What's the probability that, upon tossing a fair coin 100 times, 17 heads are obtained?
(C) If the probability that it snows in any given year in San Francisco is 0.1, what is the probability that it will snow in 8 of the ten years of the 2010's?
(A) 6C3* 5^3/6^3
(B) (100C17)/2^100
(C) (10C8)/10^8
Archived Topic
Hi there,
This topic has been closed and archived due to inactivity or violation of community quality standards. No more replies are possible here.
Where to now? Join ongoing discussions on thousands of quality questions in our Quantitative Questions Forum
Still interested in this question? Check out the "Best Topics" block above for a better discussion on this exact question, as well as several more related questions.
Thank you for understanding, and happy exploring!
