Calculating Theoretical Probability
Calculating theoretical probability is a Grade 7 math skill in Big Ideas Math Advanced 2, Chapter 15: Probability and Statistics. When all outcomes are equally likely, theoretical probability equals the number of favorable outcomes divided by the total number of possible outcomes. For example, the probability of rolling a 2 on a six-sided die is 1/6 because there is 1 favorable outcome out of 6 possible outcomes.
Key Concepts
When all outcomes in a sample space are equally likely, the theoretical probability of an event is: $$ P(\text{event}) = \frac{\text{Number of Favorable Outcomes}}{\text{Total Number of Possible Outcomes}} $$.
Common Questions
How do you calculate theoretical probability?
Divide the number of favorable outcomes by the total number of possible outcomes. All outcomes must be equally likely. For example, P(drawing a red marble) equals 4 divided by 10 if there are 4 red and 6 blue marbles.
What is the difference between theoretical and experimental probability?
Theoretical probability is calculated mathematically based on equally likely outcomes. Experimental probability is calculated from actual experimental data and may differ from the theoretical value.
What does a probability of 1/2 mean?
A probability of 1/2 means there is an equal chance of the event happening or not happening. For example, flipping a fair coin has a theoretical probability of 1/2 for heads.
What textbook covers calculating theoretical probability in Grade 7?
Big Ideas Math Advanced 2, Chapter 15: Probability and Statistics covers calculating theoretical probability for simple and compound events.