Answers

2014-08-13T20:26:21+08:00
19 2/3-4 = 15 2/3
16 3/5-9 = 7 3/5
24 7/10-18 = 6 7/10,
42 3/4- 16 = 26 3/4
20 4/6 -8 = 12 4/6 or 12 2/3
0
2014-08-13T20:28:55+08:00
15 2/3
7 3/5 
6 7/10
26 3/4
12 2/3
1 1 1
15 2/3
15 2/3, 7 3/5, 6 7/10, 22 3/4, 12 4/6 or 12 2/3