CCSS.Math.Content.HSS-MD.B

MathGrades 9–12Using Probability to Make Decisions

The standard

Use probability to evaluate outcomes of decisions

Common Core State Standards for Mathematics · High School — Statistics and Probability

What this standard means

Students need to use probabilities, expected values, and payoff tables to compare choices. They should connect a chance model to a real decision, then explain which option is better and why. The math is not just finding a probability. It is using that probability to justify an action.

Mastery looks like a student building or reading a table of outcomes, multiplying payoffs by probabilities, and comparing long-run results. Students often get stuck treating the most likely outcome as the best choice, ignoring rare but costly outcomes, or mixing up experimental probability with a stated probability model.

Ways to teach it

  • Use a spinner, play-money payouts, and a payoff table so students test which game is better over 20 spins.
  • Ask students to write: Would you buy the warranty, and what probability or cost would change your mind?
  • Give a two-option payoff table and have students compute expected value, then choose the better option in three minutes.
  • Compare two phone insurance plans using monthly cost, deductible, replacement price, and estimated chance of damage.

Plan a lesson for CCSS.Math.Content.HSS-MD.B

Generate a complete lesson plan aligned to this standard, with objectives, activities, and materials. Free, no account needed.

Related standards

Standard text verified against corestandards.org on July 10, 2026.

Page updated July 10, 2026.

Send Feedback