Comments on: Math problem of the day http://www.26econ.com/math-problem-of-the-day/ Online economics Fri, 21 Nov 2008 01:04:30 +0000 http://wordpress.org/?v=2.3.2 By: MacKenzie http://www.26econ.com/math-problem-of-the-day/#comment-17650 MacKenzie Mon, 17 Nov 2008 05:46:54 +0000 http://www.26econ.com/math-problem-of-the-day/#comment-17650 (1/100)exp(99)= 1.0 x 10exp(-200) would be the equation and solution to find the probability of a repete within one hundred plays. Any more than 100 plays and there would automatically be a repete. (1/100)exp(99)= 1.0 x 10exp(-200) would be the equation and solution to find the probability of a repete within one hundred plays. Any more than 100 plays and there would automatically be a repete.

]]> By: Andy http://www.26econ.com/math-problem-of-the-day/#comment-13837 Andy Sat, 18 Oct 2008 13:54:34 +0000 http://www.26econ.com/math-problem-of-the-day/#comment-13837 song odds of odds of first a repeat listen 1 1 1.00 2 0.99 0.99 3 0.98 0.97 4 0.97 0.94 5 0.96 0.90 6 0.95 0.86 7 0.94 0.81 8 0.93 0.75 9 0.92 0.69 10 0.91 0.63 11 0.9 0.57 12 0.89 0.50 13 0.88 0.44 so we have a 50-50 change of getting a repeat on the 12th song song odds of odds of
first a repeat
listen
1 1 1.00
2 0.99 0.99
3 0.98 0.97
4 0.97 0.94
5 0.96 0.90
6 0.95 0.86
7 0.94 0.81
8 0.93 0.75
9 0.92 0.69
10 0.91 0.63
11 0.9 0.57
12 0.89 0.50
13 0.88 0.44

so we have a 50-50 change of getting a repeat on the 12th song

]]> By: aaron http://www.26econ.com/math-problem-of-the-day/#comment-192 aaron Fri, 05 Oct 2007 13:26:02 +0000 http://www.26econ.com/math-problem-of-the-day/#comment-192 Gabriel: Nice guess, but no it's not 100. In fact it's almost impossible to listen to all 100 songs without encountering a repeat. Assuming we got to the last song with no repeats, there's only a 1/100 chance that it doesn't repeat any of the 99 previous songs. And the 99th song only has a 2/100 chance of not being a repeat, etc. So the probability of getting to 100 with no repeats is 99! / (100^99) = 0.00000000000000000000000000000000000000000093, according to my computer. Gabriel: Nice guess, but no it’s not 100. In fact it’s almost impossible to listen to all 100 songs without encountering a repeat. Assuming we got to the last song with no repeats, there’s only a 1/100 chance that it doesn’t repeat any of the 99 previous songs. And the 99th song only has a 2/100 chance of not being a repeat, etc. So the probability of getting to 100 with no repeats is 99! / (100^99) = 0.00000000000000000000000000000000000000000093, according to my computer.

]]> By: Gabriel http://www.26econ.com/math-problem-of-the-day/#comment-191 Gabriel Fri, 05 Oct 2007 08:26:48 +0000 http://www.26econ.com/math-problem-of-the-day/#comment-191 OK, I know it's wrong, but let me just try it... 100? OK, I know it’s wrong, but let me just try it… 100?

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