1.выполни устные вычисления и сделай проверку.
19 + 19 =
32 + 28 =
67 - 49 =
83 - 27 =
64 +17 =
37 + 46 =
43 - 24 =
42 - 35 =
84 - 48 =
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1. 19+19 = 38

38-19 = 19

2. 32+28 = 60

60-28 = 32

3. 67-49 = 18

18+49 = 67

4. 83-27 = 56

56+27 = 83

5. 64+17 = 81

81-17 = 64

6. 37+46 = 83

83-46 = 37

7. 43-24 = 19

19+24 = 43

8. 42-35 = 7

7+35 = 42

9. 84-48 = 36

36+48 = 84