Correction :

9 × 10 = 90	30 - 6 = 24
6 + 8 = 14	13 - 1 = 12
18 + 18 = 36	3 × 6 = 18
6 + 9 = 15	5 + 7 = 12
21 + 17 = 38	27 - 21 = 6
5 × 4 = 20	18 + 19 = 37
0 + 11 = 11	4 × 2 = 8
17 + 21 = 38	29 - 21 = 8
6 + 3 = 9	99 : 9 = 11
47 - 24 = 23	21 + 8 = 29