Correction :

20 + 23 = 43	42 - 18 = 24
19 + 14 = 33	32 - 20 = 12
13 + 3 = 16	24 - 13 = 11
23 + 4 = 27	28 - 9 = 19
24 + 20 = 44	40 - 21 = 19
21 - 2 = 19	44 - 23 = 21
30 - 24 = 6	16 + 11 = 27
18 + 9 = 27	34 - 12 = 22
26 - 24 = 2	23 + 5 = 28
28 - 10 = 18	13 + 12 = 25