# Probability Rules Practice Questions

Questions

1.) An event has a 25% chance of occurring. What is the chance of it not occurring? What rule did you use to determine this?

2.) Event A has a 50% chance of occurring, and Event B has a 50% chance of occurring. What is the probability that Event A or Event B occurs, assuming that they are NOT mutually exclusive? What rule did you use to determine this?

3.) Event A has a 50% chance of occurring, and Event B has a 50% chance of occurring. What is the probability that Event A and Event B occurs, assuming that the events are independent? What rule did you use to determine this?

4.) 2.) Event A has a 50% chance of occurring, and Event B has a 50% chance of occurring. What is the probability that Event A or Event B occurs, assuming that they are mutually exclusive? What rule did you use to determine this?

5.) An event has a 5% chance of occurring. What is the chance of it not occurring? What rule did you use to determine this?

6.) Event A has a 10% chance of occurring, and Event B has a 10% chance of occurring. What is the probability that Event A and Event B occurs, assuming that the events are independent? What rule did you use to determine this?

7.) An event has a 80% chance of occurring. What is the chance of it not occurring? What rule did you use to determine this?

8.) Event A has a 60% chance of occurring, and Event B has a 60% chance of occurring. What is the probability that Event A and Event B occurs, assuming that the events are independent? What rule did you use to determine this?

9.) Event A has a 20% chance of occurring, and Event B has a 20% chance of occurring. What is the probability that Event A or Event B occurs, assuming that they are NOT mutually exclusive? What rule did you use to determine this?

10.) Event A has a 20% chance of occurring, and Event B has a 20% chance of occurring. What is the probability that Event A or Event B occurs, assuming that they are mutually exclusive? What rule did you use to determine this?

1.) 75% – Complement Rule

3.) 25% – Multiplication Rule