Assessment and Learning in Knowledge Spaces (ALEKS) Practice Exam

In probability, what does it mean when an event is described as independent?

1. The outcome of one event affects the outcome of another

2. The outcome of one event is completely random

3. The probability of an event is always less than 1

4. The outcome of one event does not affect the outcome of another

The correct answer is: The outcome of one event does not affect the outcome of another

When an event is described as independent in probability, it means that the occurrence of one event does not influence or alter the likelihood of another event occurring. This is a fundamental concept in probability theory and is critical when calculating probabilities for combined events. For example, consider flipping a coin and rolling a die. The outcome of flipping the coin (heads or tails) has no bearing on the result of rolling the die (which could land on any number from 1 to 6). Therefore, these events are independent of each other. When determining the probability of two independent events happening together, the probability of both events can be calculated by multiplying their individual probabilities. This concept is important because it allows us to simplify complex probability scenarios by treating independent events separately.