additions
12 + 12
24
900 - 200
700
3/4 - 2/4
1/4
5/5 + 3/3
8/8
4 x 4
16
4 + 8
12
400 - 200
200
8/8 - 5/5
3/3
10/10 + 9/9
19/19
4 x 8
32
45 + 2
47
2,000 - 1,000
1,000
9/9 - 1/1
8/8
6/6 + 6/6
12/12
3 x 10
30
99 + 1
100
300 - 200
100
10/10 - 2/2
8/8
20/20 + 10/10
30/30
4 x 5
20
100 + 200
300
7,000 - 5,000
2,000
12/12 - 3/3
9/9
100/100 + 500/500
600/600
12 x 3
36