Wizard correct on craps point numbers in FAQ??
"On average, during the course of 100 points being established in craps: (1) How many of those would be 4/10, 5/9 or 6/8, (2) During the 100 how many times would each point (4/10, 5/9, 6/8) vs. a 7 being rolled. Jon Moriarty from Danville, New Hampshire
Of those 100 points established, on average 45.45 would be on a 6 or 8, 40 would be on a 5 or 9, and 33.33 would be on a 4 or 10. You could expected on average 18.94 points made on a 6 or 8, 13.33 on a 5 or 9, and 8.33 on a 4 or 10. Jan. 14, 2001"
Out of 100 points, how can 45.45 be 6/8, 40 be 5/9, and 33.33 be 4/10?? That adds up to over 100 points! Even if those were probabilities instead of hard numbers, they still add up to more than 100%. Am I not seeing something here?
Quote: IAchance5Hi, I love wizard of odds website and it has a lot of great info, but I was reading the craps FAQ on probability and it states:
"On average, during the course of 100 points being established in craps: (1) How many of those would be 4/10, 5/9 or 6/8, (2) During the 100 how many times would each point (4/10, 5/9, 6/8) vs. a 7 being rolled. Jon Moriarty from Danville, New Hampshire
Of those 100 points established, on average 45.45 would be on a 6 or 8, 40 would be on a 5 or 9, and 33.33 would be on a 4 or 10. You could expected on average 18.94 points made on a 6 or 8, 13.33 on a 5 or 9, and 8.33 on a 4 or 10. Jan. 14, 2001"
Out of 100 points, how can 45.45 be 6/8, 40 be 5/9, and 33.33 be 4/10?? That adds up to over 100 points! Even if those were probabilities instead of hard numbers, they still add up to more than 100%. Am I not seeing something here?
Even wizards make mistakes. total and winner 41.67 and 18.94 for 6/8, 33.33 and 13.33 for 5/9, 25 and 8.33 for 4/10
I was about to say that I think you found some typos.
Then I started to work the math:
24 out of 36 come out rolls are points, so only 24 rolls matter.
Out of those 24 rolls, 6 will be 4 or 10, 6/24 =.25
Out of those 24 rolls, 8 will be 5 or 9, 8/24 =.33
Out of those 24 rolls, 10 will be 6 or 8, 10/24=.42
Once a point is established, all rolls other than the point and 7 don't matter, so the odds of hitting the point vs 7 is calcuated by the combinations of the point, divided by those combinations plus the six combinations of 7.
Point of 4 or 10: 3/9=.33
Point of 5 or 9: 4/10=.40
Point of 6 or 8: 5/11=.45
You then multiply those two sets to find out the chance of a particular point pair hitting and then winning:
4 or 10: .25*.33=.0833
5 or 9 : .33*.40=.1333
6 or 8 : .42*.45=.1894
The Wiz's numbers are right. It's his description that could use a little tweaking.
