Original: 40 hours

New: 32.5 hours

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

The amount of change = New hours – Original hours.

 The hours 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 decrease by 18.75%

The percent of change is a percent of decrease.

The percentage of decrease by 18.75%.