Single Rule of Three Calculator

The formula is X = (B × C) ÷ A. Multiply the second known value by the third known value, then divide the product by the first known value.

Use it when two quantities have a constant direct relationship. For example, if the price of an item stays the same, buying twice as many items costs twice as much.

Yes. The calculator supports decimal values, making it suitable for measurements, prices, weights, distances, and other proportional calculations.

No. Direct proportion means both quantities increase or decrease together at a constant ratio. Inverse proportion means one quantity increases as the other decreases, such as the time required to complete a fixed task when the number of equally productive workers changes.

Yes. If the second or third value is zero, the calculated result is zero. The first value cannot be zero because the formula requires division by that value.