Three-stage counting principle, step by step

Three mains, two sides and four drinks make twenty-four meals.

The question

9 mains, 3 sides and 7 drinks. How many different meals can you make?

9 mains, 3 sides and 7 drinks. How many different meals can you make?

937
9×3=27
27×7=189
  1. Each of the 9 mains can go with every one of the 3 sides, so the choices multiply — they do not add.
  2. First two stages: 9 × 3 = 27.
  3. Then the 7 drinks: 27 × 7 = 189.

How it works.

  1. 01

    Each of the 9 mains can go with every one of the 3 sides, so the choices multiply — they do not add.

  2. 02

    First two stages: 9 × 3 = 27.

  3. 03

    Then the 7 drinks: 27 × 7 = 189.