Solve for the missing term

Proportions express the same relative relationship on two scales. After you enter a, b, and c, the tool finds x so that the two ratios match. Division by zero is rejected. Watch units: all four quantities should represent the same kind of measure when applied to real problems.

Finds x so that a : b = c : x

FAQ

What proportion form is used?

a : b = c : x, solved as x = b×c÷a when a ≠ 0.

Why is a = 0 rejected?

Division by zero; the ratio a : b would not define a scale.

Units and meaning

Keep a,b,c in consistent units (e.g., all lengths) so x is interpretable.

Fractions and decimals

Decimals are fine; the tool uses floating-point math—tiny rounding noise can appear in extreme cases.

Cross-multiplication intuition

Equal ratios mean the relative scale from a to b matches c to x.

Privacy

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