A, 33 + 16 = 49 B, 42 + 17 = 59C, 68 - 5 = 63 D, 23 + 15 = 38

Bài 1:a, 33 + 16 = 49 b, 42 + 17 = 59c, 68 - 5 = 63 d, 23 + 15 = 38