Original: 40

New: 32.5

Since the new amount is greater than the original, this is a percent of increase.

The amount of change = New Amount – Original Amount.

 The amount of change = .

Let r be the percentage of decrease.

Use the original number, 40 as the base.

The percent proportion is

To solve for r, first find the cross products.

                                    (Multiply: )

                             (Divide each side by 40)

                                        (Cancel common terms)

                                       (Divide: )

The percentage of increase by 18.75%

The percent of change is a percent of increase.

The percentage of increase by 18.75%.