Correction :

14 - 13 = 1	24 + 3 = 27
16 + 22 = 38	10 × 5 = 50
28 - 12 = 16	39 - 19 = 20
17 + 13 = 30	4 × 8 = 32
18 + 3 = 21	20 - 17 = 3
14 - 6 = 8	19 - 7 = 12
10 : 10 = 1	22 + 3 = 25
11 - 11 = 0	30 - 6 = 24
47 - 24 = 23	22 - 2 = 20
9 + 8 = 17	17 + 23 = 40