Percentage increase can be found by the following equation:
(new cost / old cost) - 1 = percentage increase
Plug the values in.
(2.80/2.45) - 1 = percentage increase
1.1428 - 1 = 0.1428
Convert the decimal to a percentage.
0.1428 = 14.28%
Rounded to the tenth spot, the percentage increase is 14.3%.
