Which of the following describes a simple event?
A. Drawing a three from a deck of cards and rolling 2 on a die
B. Tossing 3 coins and getting tails once
C. Rolling a die and getting a 2
D. Spinning red on a spinner and rolling an odd number on a die
The Correct Answer and Explanation is:
The correct answer is C. Rolling a die and getting a 2.
Explanation:
In probability theory, a simple event is an event that consists of only one outcome from the sample space of a probability experiment. The sample space is the set of all possible outcomes that can occur during the experiment.
Let’s examine each option:
- A. Drawing a three from a deck of cards and rolling a 2 on a die:
This is a compound event because it involves two separate events happening together: drawing a three from a deck of cards and rolling a 2 on a die. A compound event consists of more than one simple event occurring at the same time. - B. Tossing 3 coins and getting tails once:
This is also a compound event because tossing three coins creates multiple possible outcomes (e.g., Tails-Tails-Heads, Heads-Tails-Heads, etc.). Getting tails once is just one of many possible outcomes. It requires a combination of individual outcomes from tossing the three coins. - C. Rolling a die and getting a 2:
This is a simple event. The act of rolling a die results in one of the six faces showing up. A simple event is a single outcome from the sample space, and rolling a 2 is a single outcome (one specific result out of the six possible outcomes when a fair die is rolled). - D. Spinning red on a spinner and rolling an odd number on a die:
This is another compound event, as it involves two independent events: spinning a red on a spinner (which could be one of several sections, depending on the spinner’s design) and rolling an odd number on a die. Since both involve multiple outcomes, it cannot be considered a simple event.
In conclusion, C is the correct answer because it involves a single outcome (rolling a 2) from the sample space of rolling a die, which makes it a simple event.