What is Rule of 3 Calculator?

A rule of 3 calculator is a tool used to solve simple proportional math problems. It is used when you know 3 values and need to calculate the 4th value based on the proportional relationship between them.

For example, if you know that 5 units cost $10, and you want to know how much 12 units will cost, you can use the rule of 3. You enter 5 as the first value, 10 as the second value, and 12 as the third value. The calculator will determine that if 5 units costs $10, then the proportional price for 12 units is $24.

It works by cross multiplying the values. So in the example above, it calculates:

• First value (5) * Third value (12) = 60
• Second value (10) * Fourth value (X) = 60
• Solving this: X = 24

So a rule of 3 calculator is very useful for quick proportional math. It saves the effort of setting up the equation and doing the calculations manually. Instead, you just plug the 3 known values into the calculator, and it gives you the missing 4th value.

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