Proportion Calculator (a/b = c/d)
Solve for a missing value, check if two ratios are equal, or see the cross‑multiplication steps. Enter any three numbers (leave one empty) to compute the fourth.
First ratio (a / b)
📘 a / b
Enter any positive number. To solve for a missing term, leave exactly ONE field empty across both ratios.
Second ratio (c / d)
📐 Cross multiplication
a/b = c/d ⇒ a·d = b·c. If three values are known, the fourth is calculated automatically.
Proportion Result
Summary
Step‑by‑step
Visualization
Proportion statement
2/3 = 4/6
Cross product: 12 = 12
a/b decimal
0.66667
c/d decimal
0.66667
Cross check
Equal
Missing value
—
Cross‑multiplication steps
| Step | Operation | Result |
|---|
Formula used
2 × 6 = 3 × 4 → 12 = 12
Ratio bars (decimal values)
First ratio = 2/3 (0.667), second ratio = 4/6 (0.667)
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