- 640 : 40 + 830 = 16 + 830 = 846
- 39 - 10 - 41 = 29 - 41 = -12
- 300 - 27 - 4 = 273 - 4 = 269
- (445 - 95) : 50 = 350 : 50 = 7
- 160 + 20 - 9 = 180 - 9 = 171
- 490 - 2 : 70 = 490 - \frac{2}{70} = 490 - \frac{1}{35} = 489 \frac{34}{35}
Ответ: 846; -12; 269; 7; 171; 489 34/35