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Probability (Counting Principle)

Related Topics:
Common Core for Grade 7
Common Core for Mathematics
More Math Lessons for Grade 7


Examples, solutions, videos and lessons to help Grade 7 students learn how to find probabilities of compound events using organized lists, tables, tree diagrams, and simulation.

A. Understand that, just as with simple events, the probability of a compound event is the fraction of outcomes in the sample space for which the compound event occurs.

B. Represent sample spaces for compound events using methods such as organized lists, tables and tree diagrams. For an event described in everyday language (e.g., “rolling double sixes”), identify the outcomes in the sample space which compose the event.

C. Design and use a simulation to generate frequencies for compound events. For example, use random digits as a simulation tool to approximate the answer to the question: If 40% of donors have type A blood, what is the probability that it will take at least 4 donors to find one with type A blood?

Common Core: 7.SP.8

Suggested Learning Targets
  • I can explain that the fraction of outcomes in probability of a compound event is similar to the probability of a simple event.
  • I can use tree diagrams, frequency tables, and organized lists to determine the probability of a compound event.
  • I can identify the outcomes in a sample space.
  • I can represent probability outcomes as fractions, decimals, or percents.
  • I can design a simulation to estimate the probability of a compound event.
  • I can se a simulation to estimate the probability of a compound event.

Fundamental Counting Principle
This video explains how the fundamental counting principle can help you determine the number of possible outcomes or combinations very quickly.
The Counting Principle
This video explains how to find the number of ways an event can occur.



Examples of using the fundamental counting principle How the Fundamental Counting Principle can be used to solve counting problems? Fundamental Counting Principle.

Try the free Mathway calculator and problem solver below to practice various math topics. Try the given examples, or type in your own problem and check your answer with the step-by-step explanations.
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