Fill in the blanks with the correct number.
1. 4 + 5 = 1 + 8
2. 1 + 19 = 10 + 10
3. 2 + 1 = 1 + 2
4. 10 + 8 = 4 + 14
5. 7 + 2 = 9 + 0
6. 6 + 4 = 8 + 2
7. 4 + 4 = 7 + 1
8. 18 + 2 = 16 + 4
9. 13 + 3 = 15 + 1
10. 20 + 10 = 25 + 5
11. 16 + 1 = 10 + 7
12. 4 + 5 = 4 + 5
13. 8 + 1 = 7 + 2
14. 15 + 3 = 17 + 1
15. 9 + 10
= 16 + 3
16. 9 + 1 = 8 + 2