Correction :

18 : 9 = 2	3 × 9 = 27
66 : 11 = 6	3 : 3 = 1
9 + 9 = 18	23 - 10 = 13
7 + 11 = 18	18 + 13 = 31
5 - 5 = 0	24 + 6 = 30
13 + 14 = 27	6 + 19 = 25
13 + 11 = 24	12 - 0 = 12
24 - 16 = 8	6 × 5 = 30
14 + 8 = 22	18 + 20 = 38
21 + 13 = 34	15 - 10 = 5