mathematics Verified Precision Tool
Proportion Calculator
Solve direct and inverse proportions to find missing variable values.
Calculation Solution
X = 15
Equation: 100 / 150 = 10 / X
Mathematical Formula
Direct Proportion: A / B = C / X => X = (B * C) / A
Overview & Explanation
A proportion states that two ratios are equal. This tool solves for an unknown fourth variable in proportional equations.
How It Works
- Set up the equality equation A / B = C / X.
- Multiply B by C and divide by A.
Practical Applications
- Scale drawings.
- Converting currency rates.
- Unit conversion problems.
Worked Example: 4/8 = 12/X
Solve for X.
1
Cross Multiply
X = (8 * 12) / 4
= 24
Frequently Asked Questions
What is a proportion?
A proportion is an equation stating that two ratios are equal.
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