On Average (Posted on 2004-01-26)

	Submitted by SilverKnight
Rating: 3.7500 (4 votes)
Solution:	(Hide)
If the probability of an event is P then the average number of trials to achieve one of those events is 1/P. We can describe the problem in terms of 6 independent events: We get any number. We get any number besides the number in (1). We get any of the four remaining numbers. We get any of the three remaining numbers. We get any of the two remaining numbers. We get the remaining number. The probabilities are: 6/6, 5/6, 4/6, 3/6, 2/6, and 1/6 therefore the expected number of rolls to see each are: 6/6, 6/5, 6/4, 6/3, 6/2, and 6/1, respectively. x = 6/6 + 6/5 + 6/4 + 6/3 + 6/2 + 6/1 x = 1 + 1.2 + 1.5 + 2 + 3 + 6 x = 14.7

	Subject	Author	Date
	Answer	K Sengupta	2007-05-04 15:04:13
	A solution	Vincent	2004-03-09 14:15:17
	re(2): solution	Charlie	2004-01-26 23:04:56
	re: The other answers	Charlie	2004-01-26 22:44:38
	re: solution	Sam	2004-01-26 21:19:23
	re: The other answers	Penny	2004-01-26 20:42:33
	The other answers	Charlie	2004-01-26 17:28:13
	re(2): solution plus simulation-- and another question or two	Charlie	2004-01-26 14:58:49
	re: solution plus simulation-- and another question or two	SilverKnight	2004-01-26 14:12:22
	solution plus simulation-- and another question or two	Charlie	2004-01-26 14:02:07
	Solution	Federico Kereki	2004-01-26 13:16:08