TREETL
Classroom Math//v1.0/Learn something

Proportion Calculator

Solve a/b = x/d for the missing value.

Result

x

12

  1. 13/5 = x/20
  2. 2Cross-multiply: x = (a × d) ÷ b
  3. 3(3 × 20) ÷ 5 = 12
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About this instrument

Enter three known values of a proportion and TREETL finds the missing one by cross-multiplying.

What you get
  • Save time spent on repetitive calculations
  • Saves to your toolbox on any device
  • Switch currency to match yours
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Tool path

Where this fits

Part of a path: Learn something.

3 connected tools
Step 1

Proportion Calculator

Solve a/b = x/d for the missing value.

Open
Step 2

Ratio Calculator

Simplify a ratio to its lowest terms.

Open
Step 3

Unit Rate Calculator

Find the cost or amount per single unit.

Open
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