If A can happen in m ways and B in n ways, the pair can happen in m × n ways.
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Outfit: 3 shirts, 4 pants, 2 shoes
3 × 4 × 2 = 24 outfits.
If A can happen in m ways and B in n ways, the pair can happen in m × n ways.
Outfit: 3 shirts, 4 pants, 2 shoes
3 × 4 × 2 = 24 outfits.