LFD Book Forum (http://book.caltech.edu/bookforum/index.php)
-   Homework 1 (http://book.caltech.edu/bookforum/forumdisplay.php?f=130)
-   -   Question on Lecture 2 (http://book.caltech.edu/bookforum/showthread.php?t=4205)

 paul99 04-14-2013 08:42 PM

Question on Lecture 2

Hi,

In reviewing some of the lectures, I have a question about Lecture 2 (slide 14; ~ 47 minute mark), "Coin analogy", how was 63% arrived at as the answer to the second question:

If you toss 1000 fair coins 10 times each, what is the probability that some coin will get 10 heads?

Thanks,

Paul

 yaser 04-14-2013 09:10 PM

Re: Question on Lecture 2

Quote:
 Originally Posted by paul99 (Post 10404) Hi, In reviewing some of the lectures, I have a question about Lecture 2 (slide 14; ~ 47 minute mark), "Coin analogy", how was 63% arrived at as the answer to the second question: If you toss 1000 fair coins 10 times each, what is the probability that some coin will get 10 heads? Thanks, Paul
For each coin, probability of getting 10 heads is which is approximately 0.001

Therefore, for each coin, the probability of not getting 10 heads is 1 minus that, approximately 0.999

The probability that none of the 1000 coins gets 10 heads is that to the power 1000, and we approximate by since the limit of is .

Finally, the probability that at least one coin will get 10 heads is one minus that, which is and this is approximately 0.63.

PS: You can quote any part of the video lecture by using the lecture tags, in this case [lecture2] tag, as explained in the sticky thread about including a video segment.

 paul99 04-15-2013 12:33 PM

Re: Question on Lecture 2

Thanks Prof. Yaser and also for reminding me to use the post tags!

 All times are GMT -7. The time now is 10:13 PM.