Help me to do this question plz plz plz
I will make you as brainlist plz

Answer:
1. 5
2. 12
3. a. 12
3. b. 18
Step-by-step explanation:
1. 50 - 45 = 5.
2. 26 - 18 = 8. 30 - 18 = 12. 12 + 8 = 20. 20 + 18 = 38. 50 - 38 = 12.
3. a. 24 - 12 = 12.
4. 40 - 12 = 28. 24 - 12 = 12. 28 + 12 + 12 = 52. 70 - 52 = 18.