lirious
Joined: Jan 5, 2012
• Posts: 1
January 5th, 2012 at 12:31:48 PM permalink
Can someone please tell me what the probability is of rolling 5 six sided dice (all at once) and not getting a least one 1 or 5? What about when rolling 4?
How is this different than the odds given the same scenario?

Darrin
EdCollins

Joined: Oct 21, 2011
• Posts: 1312
January 5th, 2012 at 9:09:10 PM permalink
Hi Darrin,

When rolling five dice, the probability of NOT getting at least one 1 or one 5 is small... .13168 (About 13.17%)
(4/6)^5

In other words, if you are playing "Oh Shit" or "Farkle" or whatever name that dice game is going under these days, there is about an 87% chance you will roll that much needed 1 or 5, when rolling five dice.

When rolling just four dice, obviously not rolling at least one 1 or one 5 will happen more often. The probability jumps up to .19753.... about 19.75%.

(4/6)^4

If you want to know the odds, it's easy. A 20% chance, for example, will happen 1 time in 5. So the odds are 4 to 1 in your favor. (Or against you, depending upon how you look at it.)

A 13% chance will happen about 1 time in about 7.6 attempts. So the odds are 6.6 to 1 in your favor. (Or against you, depending upon what you want.)

Hope this helps.
NowTheSerpent
Joined: Sep 30, 2011
• Posts: 417
January 6th, 2012 at 4:40:11 AM permalink
Why does Farkle make it '1' or '5' instead of '1' or '6'?
Dween
Joined: Jan 24, 2010