2 + 2 =, 6 - 5 =, 9 X 2 =, 10 - 5 =, 16 / 4 =, 17 + 1 =, 19 - 4 =, 13 + 2 =, 3 X 4 =, 20 / 2 =, 14 / 7, 12 + 6 =.

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