1)
1. 24 + 10 + 23 = 57
2. 37 - 20 + 32 = 49
3. 52 - 7 + 43 = 88
4. 44 + 5 + 30 = 79
5. 45 + 25 - 20 = 50
6. 67 + 13 - 10 = 70
2)
1. 37 - 7 - 13 = 17
2. 34 - 4 - 26 = 4
3. 33 - (43 - 30) = 33 - 13 = 10
4. 55 - 5 - 7 = 43
5. 58 - 8 - 12 = 38
6. 57 - 7 - 7 = 43