Activity (Process)

Procedure for Finding Percent Increase

When a quantity grows from an original value to a larger new value, the percent increase expresses the size of that growth relative to the original value. The calculation follows two steps:

  1. Find the amount of increase by subtracting the original amount from the new amount:

new amountoriginal amount=increase\text{new amount} - \text{original amount} = \text{increase}

  1. Determine what percent the increase is of the original amount by translating the question "The increase is what percent of the original amount?" into an equation and solving it. Let pp represent the unknown percent. The equation takes the form:

increase=p×original amount\text{increase} = p \times \text{original amount}

Divide both sides by the original amount to isolate pp, then convert the resulting decimal to percent form.

The key idea is that percent increase is always calculated relative to the original (starting) amount, not relative to the new amount. This ensures a consistent basis for comparison when describing how much a quantity has grown.

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Updated 2026-04-21

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