Four shirts and three pairs of shorts make twelve outfits, not seven. These free printable worksheets count the outcomes of a choice made in stages — the multiplication rule behind every sample space.
The one idea is that independent choices MULTIPLY. Each of the four shirts can go with each of the three shorts, so the outfits are 4 × 3, not 4 + 3 — and adding is the mistake the sheet is built around. A child who pictures every shirt paired with every pair of shorts sees why it is a product.
Why this sheet works
Three stages are the same idea one step further: 3 mains, 2 sides and 4 drinks make 3 × 2 × 4 = 24 meals. The walk does it two at a time — the mains-and-sides first, then times the drinks — so the “each one with each one” stays visible instead of collapsing into a single long multiplication.
How this one works
One question from this sheet, worked through a step at a time.
8 frames and 7 wheels. How many different bikes can you make?
87
8×7=56
Each of the 8 frames can go with every one of the 7 wheels, so the choices multiply — they do not add.
8 frames and 7 wheels. How many different bikes can you make?
2
3 shirts and 6 shorts. How many different outfits can you make?
3
4 flavors, 2 cones and 3 toppings. How many different ice creams can you make?
4
2 frames, 6 wheels and 9 colors. How many different bikes can you make?
5
7 shirts, 4 shorts and 2 hats. How many different outfits can you make?
6
3 frames and 5 wheels. How many different bikes can you make?
7
3 frames, 2 wheels and 4 colors. How many different bikes can you make?
8
7 mains and 9 sides. How many different meals can you make?
The counting principle · Two and three stagesAnswer key
1. 8 frames and 7 wheels. How many different bikes can you make? → 562. 3 shirts and 6 shorts. How many different outfits can you make? → 183. 4 flavors, 2 cones and 3 toppings. How many different ice creams can you make? → 244. 2 frames, 6 wheels and 9 colors. How many different bikes can you make? → 1085. 7 shirts, 4 shorts and 2 hats. How many different outfits can you make? → 566. 3 frames and 5 wheels. How many different bikes can you make? → 157. 3 frames, 2 wheels and 4 colors. How many different bikes can you make? → 248. 7 mains and 9 sides. How many different meals can you make? → 63