Math

Proportion Calculator

Solve a/b = c/x for x.

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This free Proportion Calculator covers Solve a/b = c/x for x.

Cross-multiply to solve a proportion. Related math tools sit beside How it works, with no account required.

Using the Proportion Calculator

Solve a/b = c/x for x. Typical inputs are a, b and c. How it works beside the form states the identity the Proportion Calculator applies.

FAQ

How do I use the Proportion Calculator?

Open the Proportion Calculator, fill a, b and c, and read the result. Enter a, b, and c for the Proportion Calculator; use finite values in the indicated domain. The calculator reports x: Cross-multiply to solve a proportion. a must be nonzero because it is the divisor used to recover x.

What formula does the Proportion Calculator use?

The Proportion Calculator uses the identity in How it works. In words: Enter a, b, and c for the Proportion Calculator; use finite values in the indicated domain. The calculator reports x: Cross-multiply to solve a proportion. a must be nonzero because it is the divisor used to recover x.