7.05% is the same as the decimal 0.0705 after you move the decimal point 2 spots to the left. It's like saying 20% = 0.20; any percentage is that value over 100 so 7.05% = (7.05)/100 = 0.0705
After you get this decimal value, you multiply it by 225 to get 0.0705*225 = 15.8625 and then you round to the nearest penny to get 15.86
Answer: 15.86