Question

In a game, if you roll a 1 on a 6-sided number cube, you lose a turn.

(a) What is the probability that you roll a 1? Explain your reasoning.
(b) What is the probability that you either roll a 1 or do not roll a one? Explain your reasoning.
(c) What is the probability that you don't roll a 1? Explain your reasoning.

Answer:

Answer 1

(a) The probability of rolling a 1 on a 6-sided number cube is

1/6

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. This is because there is 1 outcome that results in a 1 (rolling a 1) and there are 6 total possible outcomes.

(b) The probability that you either roll a 1 or do not roll a 1 is 1. This is because there are no other possible outcomes. You either roll a 1 or you don't.

(c) The probability that you don't roll a 1 is 6/5

​

. This is because there are 5 outcomes that do not result in a 1 (rolling a 2, 3, 4, 5, or 6) and there are 6 total possible outcomes.

Explanation:

Answer 2

(a) The probability of rolling a 1 on a 6-sided number cube is 1/6. There is only one way to roll a 1, and there are six possible outcomes.
(b) The probability of rolling a 1 or not rolling a 1 is 1. There are only two possible outcomes, and one of them must occur.
(c) The probability of not rolling a 1 is 5/6. There are five ways to not roll a 1 (rolling a 2, 3, 4, 5, or 6), and there are six possible outcomes.