7-8-42:7 9.9-9.3 36:4+27 50-21:3

1. 7 × 8 - 42 : 7 = 56 - 6 = 50
2. 9 × 9 - 9 × 3 = 81 - 27 = 54
3. 36 : 4 + 27 = 9 + 27 = 36
4. 50 - 21 : 3 = 50 - 7 = 43

Ответ: 50; 54; 36; 43.