Wzór: p% = p/100 Przykłady: 30% = 30/100 = 3/10, 30% = 30:100 = 0,3, 45% = 45/100 = 9/20, 45% = 45:100 = 0,45, 6% = 6/100 = 3/50, 6% = 6:100 = 0,06.