Yahoo Answers is shutting down on May 4th, 2021 (Eastern Time) and beginning April 20th, 2021 (Eastern Time) the Yahoo Answers website will be in read-only mode. There will be no changes to other Yahoo properties or services, or your Yahoo account. You can find more information about the Yahoo Answers shutdown and how to download your data on this help page.
Trending News
Dice probabilities and calculations?
How do I calculate the probabilities for rolling a certain number on 2 standard dice? Specifically:
1. The probability of rolling at least one 8 in 2 throws?
2. The probability of rolling exactly one 8 in 2 throws?
3. The probability of rolling no 8's in 60 throws?
4. The probability of rolling 8 60 times in a row?
:-) Thanks!
1 Answer
- 1 decade agoFavorite Answer
You first need to know that there is a 5/36 probability of rolling an eight on any throw. This is because there are 36 total outcomes for the dice and the following yield an eight:
2,6
3,5
4,4
5,3
6,2
1. The probability that you roll at least one eight in two throws is one minus the probability that you roll no eights. The probablity that the first throw is not eight is 1-5/36=31/36. Same for the second throw. So the answer is 1-((31/36)*(31/36)).
2. The probability that the first throw is eight and the second is not is: 5/36*31/36. The probability that the first throw is not an eight and the second is an eight is the same. So the answer is 5/36*31/36+5/36*31/36=2*5/36*31/36.
3. Same reasoning as in 2: 1-(31/36)^60.
4. For each throw, there is a 5/36 probability of rolling an eight. So (5/36)^60.