Proportion Solver
Solve a proportion: if a/b = c/x, find x. Cross-multiplication solver.
X
12.0000
Ratio Left0.750000
Ratio Right0.750000
How to Solve a Proportion
Setup
a/b = c/x
Cross-Multiplication
a × x = b × c
x = (b × c) / a
Verification
After solving, check that a/b equals c/x.
Example Calculation
If 3/4 = 9/x, find x.
- 013/4 = 9/x
- 02Cross multiply: 3x = 4 × 9 = 36
- 03x = 36/3 = 12
- 04Check: 3/4 = 0.75, 9/12 = 0.75
Frequently Asked Questions
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