Correction :

32 - 20 = 12	1 × 3 = 3
23 - 18 = 5	31 - 17 = 14
17 + 0 = 17	19 - 16 = 3
1 + 17 = 18	7 - 7 = 0
17 - 4 = 13	5 + 13 = 18
9 + 24 = 33	27 - 23 = 4
24 + 23 = 47	38 - 18 = 20
27 - 19 = 8	19 + 19 = 38
26 - 20 = 6	17 + 14 = 31
12 + 18 = 30	7 + 7 = 14