Ratio Calculator

Solve a proportion of the form a : b = c : d to find the missing fourth value. Enter a, b and c to see d when you calculate.

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Solve a proportion of the form a : b = c : d to find the missing fourth value. Enter a, b and c to see d when you calculate.

Worked example

Example calculated from the starting values. Enter your own values and press Calculate to get your result.

D15.0000

With the default inputs (A = 2, B = 3, C = 10), the results are: D 15.0000.

Reference table based on the example values; it is not your calculation result.

What formula does this calculator use?

D = b × c ÷ a. Variables: a = a, b = b, c = c.

What do I need to enter?

You need a, b, c. Results update as you type.

What is an example result?

With the default inputs (A = 2, B = 3, C = 10), the results are: D 15.0000.

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