

Subject:
Probability: Two sixsided dice, rolling two numbers in order.
Category: Reference, Education and News > Homework Help Asked by: unknownentityga List Price: $10.00 
Posted:
19 Nov 2006 14:42 PST
Expires: 19 Dec 2006 14:42 PST Question ID: 784083 
Given two ordinary sixsided dice, what is the probability of rolling a 3 and a 4 in that order? I know this formula is needed: P(E)=n(E)/n(S) I'm not sure how to work the problem out. Any help is greatly appreciated.  
 


Subject:
Re: Probability: Two sixsided dice, rolling two numbers in order.
Answered By: mvguyga on 19 Nov 2006 18:00 PST Rated: 
OK, I'll use the "brute force" method. Basically, then, to restate the question, what you'll want is the chance that the two dice will add to three on the first throw, then add to four on the second throw. They are independent events, so to find the probability both will happen in that order, you multiply the two probabilities. First of all, when you throw two dice, there are 36 possible results (6 times 6), like this: 1 1 1 2 = 3 1 3 = 4 1 4 1 5 1 6 2 1 = 3 2 2 = 4 2 3 2 4 2 5 2 6 3 1 = 4 3 2 3 3 3 4 3 5 3 6 4 1 4 2 4 3 4 4 4 5 4 6 5 1 5 2 5 3 5 4 5 5 5 6 6 1 6 2 6 3 6 4 6 5 6 6 You can see the above graphically on the following page: Dice and the laws of probability http://www.edcollins.com/backgammon/diceprob.htm Of those, there are only two combinations that will give you a total of three. They are that the first die will be 1 and the second one 2, and that the first die will be 2 and the second one 1. So the chance of getting a total of 3 by throwing two dice is 2/36 or 1/18. Next, when you throw two dice, there are three ways that you can get a total of 4. They are first die 1, second die 3; first die 2, second die 2; and first die 3, second die 1. So the chance that throwing two dice will give you a total of 4 is 3/36 or 1/12. To determine the chances of getting a total of 3 and then a total of 4, you multiply the probabilities. So you'd multiply 1/18 times 1/12, to get a probability of 1/216 or 0.004629629629629629629629629... (that's a repeating number there). I think I have made it as clear as possible how I arrived at this answer. But if I didn't, please let me know. Sincerely, Mvguyga 
unknownentityga
rated this answer:
You're brilliant :). 

Subject:
Re: Probability: Two sixsided dice, rolling two numbers in order.
From: ansel001ga on 19 Nov 2006 16:01 PST 
Are you talking about rolling a three with the first die and then a four with the second die? Or are you talking about rolling a total of three with the two dice and then a four with the two dice? In either case, the two events are independent. So what you rolled the first time has no bearing on what you will roll next. So the probability is: P(3 then 4) = P(3) x P(4) 
Subject:
Re: Probability: Two sixsided dice, rolling two numbers in order.
From: unknownentityga on 19 Nov 2006 16:59 PST 
It's a total of three, and a total of four I would assume. 
Subject:
Re: Probability: Two sixsided dice, rolling two numbers in order.
From: ansel001ga on 19 Nov 2006 17:06 PST 
There are six possible numbers on each of two dice, so the number of possible rolls is 6^2 or 36. You can roll a three with 1 2 or 2 1. I trust you can figure out the rest. 
Subject:
Re: Probability: Two sixsided dice, rolling two numbers in order.
From: mvguyga on 19 Nov 2006 18:34 PST 
Thanks for the kind comment and positive rating! 
If you feel that you have found inappropriate content, please let us know by emailing us at answerssupport@google.com with the question ID listed above. Thank you. 
Search Google Answers for 
Google Home  Answers FAQ  Terms of Service  Privacy Policy 