Expected number of tosses for n heads in a row. [on hold]











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The probability of getting a head after a coin toss is $p$. Let $t$ be the number of tosses made until we get $n$ heads in a row. What’s the expected value of $t$?






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put on hold as off-topic by Y. Forman, Mark, Rebellos, jgon, Shailesh 20 hours ago


This question appears to be off-topic. The users who voted to close gave this specific reason:


  • "This question is missing context or other details: Please improve the question by providing additional context, which ideally includes your thoughts on the problem and any attempts you have made to solve it. This information helps others identify where you have difficulties and helps them write answers appropriate to your experience level." – Y. Forman, Mark, Rebellos, jgon, Shailesh

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    What is the source of this question? This is the second time it has appeared today.
    – lulu
    yesterday










  • See here: math.stackexchange.com/questions/364038/… e=2(2^n-1)
    – Ben W
    yesterday












  • @lulu I read it in the book Mathematics in Games, Sports and Gambling, of Ronald J. Gould.
    – Sergio Enrique Yarza Acuña
    yesterday










  • The answer is $(1-p^n)/((p^n)(1-p))$ which can be derived in a number of ways. Here's one source: www2.bc.edu/ned-rosen/public/CoinFlips.pdf
    – Ned
    yesterday















up vote
-1
down vote

favorite












The probability of getting a head after a coin toss is $p$. Let $t$ be the number of tosses made until we get $n$ heads in a row. What’s the expected value of $t$?






probability







share|cite|improve this question













put on hold as off-topic by Y. Forman, Mark, Rebellos, jgon, Shailesh 20 hours ago


This question appears to be off-topic. The users who voted to close gave this specific reason:


  • "This question is missing context or other details: Please improve the question by providing additional context, which ideally includes your thoughts on the problem and any attempts you have made to solve it. This information helps others identify where you have difficulties and helps them write answers appropriate to your experience level." – Y. Forman, Mark, Rebellos, jgon, Shailesh

If this question can be reworded to fit the rules in the help center, please edit the question.









  • 2




    What is the source of this question? This is the second time it has appeared today.
    – lulu
    yesterday










  • See here: math.stackexchange.com/questions/364038/… e=2(2^n-1)
    – Ben W
    yesterday












  • @lulu I read it in the book Mathematics in Games, Sports and Gambling, of Ronald J. Gould.
    – Sergio Enrique Yarza Acuña
    yesterday










  • The answer is $(1-p^n)/((p^n)(1-p))$ which can be derived in a number of ways. Here's one source: www2.bc.edu/ned-rosen/public/CoinFlips.pdf
    – Ned
    yesterday













up vote
-1
down vote

favorite









up vote
-1
down vote

favorite











The probability of getting a head after a coin toss is $p$. Let $t$ be the number of tosses made until we get $n$ heads in a row. What’s the expected value of $t$?






probability







share|cite|improve this question













The probability of getting a head after a coin toss is $p$. Let $t$ be the number of tosses made until we get $n$ heads in a row. What’s the expected value of $t$?






probability




probability






share|cite|improve this question













share|cite|improve this question











share|cite|improve this question




share|cite|improve this question










asked yesterday









Sergio Enrique Yarza Acuña

693314




693314




put on hold as off-topic by Y. Forman, Mark, Rebellos, jgon, Shailesh 20 hours ago


This question appears to be off-topic. The users who voted to close gave this specific reason:


  • "This question is missing context or other details: Please improve the question by providing additional context, which ideally includes your thoughts on the problem and any attempts you have made to solve it. This information helps others identify where you have difficulties and helps them write answers appropriate to your experience level." – Y. Forman, Mark, Rebellos, jgon, Shailesh

If this question can be reworded to fit the rules in the help center, please edit the question.




put on hold as off-topic by Y. Forman, Mark, Rebellos, jgon, Shailesh 20 hours ago


This question appears to be off-topic. The users who voted to close gave this specific reason:


  • "This question is missing context or other details: Please improve the question by providing additional context, which ideally includes your thoughts on the problem and any attempts you have made to solve it. This information helps others identify where you have difficulties and helps them write answers appropriate to your experience level." – Y. Forman, Mark, Rebellos, jgon, Shailesh

If this question can be reworded to fit the rules in the help center, please edit the question.








  • 2




    What is the source of this question? This is the second time it has appeared today.
    – lulu
    yesterday










  • See here: math.stackexchange.com/questions/364038/… e=2(2^n-1)
    – Ben W
    yesterday












  • @lulu I read it in the book Mathematics in Games, Sports and Gambling, of Ronald J. Gould.
    – Sergio Enrique Yarza Acuña
    yesterday










  • The answer is $(1-p^n)/((p^n)(1-p))$ which can be derived in a number of ways. Here's one source: www2.bc.edu/ned-rosen/public/CoinFlips.pdf
    – Ned
    yesterday














  • 2




    What is the source of this question? This is the second time it has appeared today.
    – lulu
    yesterday










  • See here: math.stackexchange.com/questions/364038/… e=2(2^n-1)
    – Ben W
    yesterday












  • @lulu I read it in the book Mathematics in Games, Sports and Gambling, of Ronald J. Gould.
    – Sergio Enrique Yarza Acuña
    yesterday










  • The answer is $(1-p^n)/((p^n)(1-p))$ which can be derived in a number of ways. Here's one source: www2.bc.edu/ned-rosen/public/CoinFlips.pdf
    – Ned
    yesterday








2




2




What is the source of this question? This is the second time it has appeared today.
– lulu
yesterday




What is the source of this question? This is the second time it has appeared today.
– lulu
yesterday












See here: math.stackexchange.com/questions/364038/… e=2(2^n-1)
– Ben W
yesterday






See here: math.stackexchange.com/questions/364038/… e=2(2^n-1)
– Ben W
yesterday














@lulu I read it in the book Mathematics in Games, Sports and Gambling, of Ronald J. Gould.
– Sergio Enrique Yarza Acuña
yesterday




@lulu I read it in the book Mathematics in Games, Sports and Gambling, of Ronald J. Gould.
– Sergio Enrique Yarza Acuña
yesterday












The answer is $(1-p^n)/((p^n)(1-p))$ which can be derived in a number of ways. Here's one source: www2.bc.edu/ned-rosen/public/CoinFlips.pdf
– Ned
yesterday




The answer is $(1-p^n)/((p^n)(1-p))$ which can be derived in a number of ways. Here's one source: www2.bc.edu/ned-rosen/public/CoinFlips.pdf
– Ned
yesterday















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