subtraction
25-12
13
17+34
51
8x5
40
20/5
4
268-158
100
165+297
462
20x4
80
25/6
4r1
1782-1658
124
820+605
1425
60x7
420
125/20
6r5
2635-1983
652
8654+1867
10,521
453x64
28,992
125/15
8r5
12876-15743
7133
5639+1694
7333
1025x25
26625
530/80
6r50