Reverse a decrease with the remaining factor

A percentage decrease leaves only part of the original value behind. For example, a 25% decrease means the final number is 75% of the original, so the reverse step is dividing by 0.75.

Where this appears

Use this for sale-price questions, depreciation, reduced measurements, stock drops, and exam problems that give the discounted value first.

How to verify the answer

Once you find the original amount, subtract the decrease percentage from it again. The result should match the final value shown in the calculator summary.