Correction :

2 + 13 = 15	30 - 17 = 13
3 + 20 = 23	11 × 2 = 22
14 + 19 = 33	2 + 6 = 8
4 + 14 = 18	41 - 21 = 20
11 - 10 = 1	10 - 5 = 5
48 - 24 = 24	1 + 3 = 4
18 - 0 = 18	5 + 10 = 15
2 + 14 = 16	41 - 21 = 20
2 + 7 = 9	6 + 12 = 18
19 + 15 = 34	22 - 10 = 12