which of these add up to EXACTLY 20 (choose as much as needed)
4 1/6
6 2/8
7 1/2
8/10
1/4
1 2/3
8 7/11
1 1/3
1/8
4 1/6
6 2/8
7 1/2
8/10
1/4
1 2/3
8 7/11
1 1/3
1/8