Solve proportions, simplify ratios, and scale values with clear intermediate steps. Fully client-side — no account, uploads, or remote storage.
Added Apr 18, 2026
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Simplifies a ratio A:B by dividing both values by their Greatest Common Divisor (GCD). Also solves proportions: given A:B = C:?, finds the missing fourth value using cross-multiplication.
Simplified: A/GCD : B/GCD Proportion: D = B × C / A
GCD(12, 8) = 4. 12/4 = 3, 8/4 = 2 → 3:2.
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D = 6 × 10 / 4 = 60 / 4 = 15.
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Find the Greatest Common Divisor (GCD) of both numbers, then divide each by it. For example, 12:8 → GCD is 4 → divide both by 4 → 3:2.
Use cross-multiplication: if A:B = C:D, then D = (B × C) / A. For example, if 4:6 = 10:D, then D = (6 × 10) / 4 = 15.