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## Which is more likely rolling a total of 9 when two dice are rolled or rolling a total of 9 when three dice are rolled?

Which is more likely, rolling a total of 9 when two dice are rolled or rolling a total of 9 when three dice are rolled? Answer: 9 = 3+6 = 4+5 = 5+4 = 6+3, — 4 ways to get total of 9 points rolling two dice, so the probability that the outcome is 9 points is: 4/(6*6) = 1/9 = **0.111**.

## What is the probability of rolling a sum of 9 with two dice?

The probability of getting 9 as the sum when 2 dice are thrown is **1/9**.

## What is the probability of getting a sum of at least 9?

❖ “At least one” is equivalent to “one or more.” To find the probability of at least one of something, calculate the probability of none and then subtract that result from 1. That is, **P(at least one) = 1 – P(none)**.

## How many outcomes have a sum of at least 9?

(ii) two numbers appearing on them whose sum is 9. Therefore, total number of possible outcomes = **36**.

## What is the probability of rolling 3 dice?

Two (6-sided) dice roll probability table

Roll a… | Probability |
---|---|

3 | 3/36 (8.333%) |

4 | 6/36 (16.667%) |

5 | 10/36 (27.778%) |

6 | 15/36 (41.667%) |

## When three dice are rolled together what is the probability of getting at least two 5?

= **91/216**.

## What is the expected sum of the numbers that appear when three fair dice are rolled?

E(S) = E(s1+s2+s3) = E(s1)+E(s2)+E(s3). The expectation of the sum is the sum of the expectation values for the three dice. But since they are all fair dice, they have the same expectation values. Hence **E(S) = 3 E(s1)**.