Twelfth graders learn to count arrangements and selections — permutations (where order matters) and combinations (where it doesn’t) — the counting foundations behind probability, from lottery odds to team lineups.
Students will be able to…
How many ways can you arrange 3 people in a line? How many ways can you CHOOSE 3 from a group? The answers differ — because sometimes order matters and sometimes it doesn’t.
Project this and change n and r. Compare permutations (order matters) and combinations (order doesn’t) for the same choice!
Tap any phase to open the teacher moves and student actions.
Arranging 3 people in a line vs. choosing 3 from a group — different counts?
Teacher models.
Class uses Permutations vs. Combinations.
Students count.
One counting problem.
Aligned to the Common Core State Standards for Mathematics (High School · Precalculus).
Use permutations and combinations to compute probabilities.
Apply the general Multiplication Rule.
Define and use random variables.
Describe events as subsets of a sample space.
Preview the three formative checks. Tap “Sample answer” to see what mastery looks like — hide them before you print for students.
Have students use combinations to compute a real probability — like the chance of being dealt a particular hand of cards. A printable counting sheet is in the Math library.
Tap a card to flip it, then rate whether you knew it. Built from this lesson’s vocabulary.
A quick self-check with instant feedback, drawn from this lesson’s key terms.
A print-and-go review sheet with a built-in answer key. Tap “Show answer key” to reveal answers, or print the clean version for students.