12 ×
4
3
1
1
10 ×
5
2
15 ×
3
4 ÷
4
10 ×
5
2 ÷
2
1
5
1
2
12 ×
3
20 ×
4
1
20 ×
2
12 ×
3
4
5
2
5
4
3 ×
1
3