Original: 15.6

New: 11.4 \ \

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 increase.

Use the original number, 15.6 as the base.

The percent proportion is

To solve for r, first find the cross products.

                                 (Multiply: )

                          (Divide each side by 15.6)

                                       (Cancel common terms)

                                       (Divide: )

The percentage of increase by 26.92%

The percent of change is a percent of increase.

The percentage of increase by 26.92%.