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Ratios & Proportions

Write and reduce ratios, solve proportions by cross-multiplication, find unit rates, and scale recipes or blueprints.

3 parts2 parts
Ratio 3 : 2

Worked Example

Solve 3/4 = x/20

Given: Find x

  1. 1

    Cross-multiply

    3 · 20 = 4 · x

Worked Example

Scale recipe ×2.5

Given: 2 cups flour serves 4; need 10

  1. 1

    Scale factor

    10 / 4 = 2.5

Timed Game · 6 problems
02:00

Answer 6 problems in 2 min. Timer auto-stops.