8 300 : 10 – 30 = 830 - 30 = 800
36 × 1 000 + 20 = 36 000 + 20 = 36 020
200 : (310 – 300) : 5 = 200 : 10 : 5 = 20 : 5 = 4
400 : (460 – 360) × 4 = 400 : 100 × 4 = 4 × 4 = 16
61 000 – 1 = 60 999
49 099 + 1 = 49 100