trifecta3
trifecta3
  • Threads: 1
  • Posts: 1
Joined: Oct 28, 2014
October 28th, 2014 at 11:39:00 AM permalink
Hi, can someone explain what the odds are of rolling a 6 or an 8 before hitting a 7? Say I place odds on 6 and 8. What would my expected value be? I understand that the odds of rolling a 6 before a 7 is 5/11 and the odds of rolling an 8 before a 7 is 5/11. But what are the odds of rolling a 6 or 8 before 7? Thank you.
wudged
wudged
  • Threads: 2
  • Posts: 998
Joined: Aug 7, 2013
October 28th, 2014 at 11:52:42 AM permalink
10/16
sodawater
sodawater
  • Threads: 64
  • Posts: 3321
Joined: May 14, 2012
October 28th, 2014 at 12:34:18 PM permalink
Quote: trifecta3

Hi, can someone explain what the odds are of rolling a 6 or an 8 before hitting a 7? Say I place odds on 6 and 8. What would my expected value be? I understand that the odds of rolling a 6 before a 7 is 5/11 and the odds of rolling an 8 before a 7 is 5/11. But what are the odds of rolling a 6 or 8 before 7? Thank you.



The chance of hitting at least one 6 or 8 before sevening out is 10/16.

The expected values of your odds bets are $0.00.
Bohemian
Bohemian
  • Threads: 9
  • Posts: 198
Joined: Apr 18, 2013
October 29th, 2014 at 9:20:52 AM permalink
Depends if you are playing in an Indian Casino or not.
Romes
Romes
  • Threads: 29
  • Posts: 5600
Joined: Jul 22, 2014
October 29th, 2014 at 11:31:46 AM permalink
Quote: Bohemian

Depends if you are playing in an Indian Casino or not.


+1

10/16... (5+5 / 5+5+6)

Although they've already given you your answer, and info on your odds addition, I for some reason enjoy doing craps math and was already writing this out on my own because I wanted to... So I guess I'll share the expected value of this situation (assuming your place bets on 6/8 are 1 'unit') in case there was possibly a follow up to it or if anyone would be curious, such as myself.

EV = P(6) + P(8) - P(7)
EV = (5/36)(1)(7/6) + (5/36)(1)(7/6) - (6/36)(-2)

EV = (.13889)(1.16667) + (.13889)(1.16667) - (.16667)(-2)

EV = .16204 + .16204 - .33334

EV = -.00926 = -.93% (per role)
Playing it correctly means you've already won.
bahdbwoy
bahdbwoy
  • Threads: 14
  • Posts: 163
Joined: Aug 23, 2013
November 1st, 2014 at 4:46:23 AM permalink
dont get confused on per res vs per roll...
hmm sounds familiar...
for your reading pleasure.. or torture
https://wizardofvegas.com/forum/gambling/craps/18390-weird-dumb-question-about-odds/8/#post389014

ev tells all

place 6
win 5/36 * 7 = .97
lose 6/36 * 6 = 1
total = .03
.03/6 = .005
or .02778/6 = .00463 per dollar wagered

place 6/8
win 10/36 * 7 = 1.94
lose 6/36 * 12= 2
total = .06 (we have two place bets so /2 =.03)
.06/12 = .005
or .05556/12 = .00463 per dollar wagered
  • Jump to: