1. x + 19 = 24
2. 10 = s + 3
3. r + 11 = 50
4. q – 8 = 9
5. 3 = y – 16
6. b – 13 = 18
7. a + 17 = 42
8. 12 + n = 28
9. 15 = x – 7
10. m – 24 = 9
11. 39 = e – 2
12. z + 68 = 77

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