402 * 350 / 40 = 201 * 35 / 2 = 100. 5 * 35 = 3517.5
4020 ˣ 3500 - ₊2010000 1206- 14070000 14070000|_40⁻120 351750- 207 ⁻200 - 70 ⁻40 - 300 ⁻280 - 200 ⁻200 - 0