23 - 9 + 14 =, 96 - 77 + 19 =, 65 - 19 + 46 =, 67 - 29 + 38 =, 55 - 29 + 26 =, 64 - 45 + 19, 85 - 49 + 36 =, 82 - 73 + 9 =, 53 - 39 + 14 =, 18 - 9 + 9 =,

Mental addition strategy: compensating. Round up numbers like 19 to an 'easy' 20, add it on, then subtract 1 from total.

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