3 2/5-2 1/5=1 1/5
5 3/7-1 1/7=4 2/7
2 4/5-2/5=2 2/5
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5-3 4/5=4 5/5-3 4/5=1 1/5
3-5/7=2 7/7-5/7=2 2/7
1-3/4=4/4-3/4=1/4
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3 2/5-1 3/5=2 7/5-1 3/5=1 4/5
5 4/9-3 5/9=4 13/9-3 5/9=1 8/9
2 2/9-5/9=1 11/9-5/9=1 6/9=1 2/3
6 2/7-6/7=5 9/7-6/7=5 3/7