1) 3/7 + 4/9 = 61/632) 8/9 - 7/8 = 17/723) 13/15 - 2/3 = 1/154) 20/21 + 3/7 = 167/1475) 17/18 - 11/12 = 1/366) 7/16 + 1/6 = 13/247) 2/9 + 5/6 = 23/188) 10/21 + 9/14 = 23/149) 7/9 - 4/15 = 71/4510) 9/14 - 3/7 + 15/28 = 13/2111) 1/6 + 1/4 - 1/8 = 7/1212) 13/18 - 29/45 + 8/15 = -1/2
1) 3/7 + 4/9 = 61/63
2) 8/9 - 7/8 = 17/72
3) 13/15 - 2/3 = 1/15
4) 20/21 + 3/7 = 167/147
5) 17/18 - 11/12 = 1/36
6) 7/16 + 1/6 = 13/24
7) 2/9 + 5/6 = 23/18
8) 10/21 + 9/14 = 23/14
9) 7/9 - 4/15 = 71/45
10) 9/14 - 3/7 + 15/28 = 13/21
11) 1/6 + 1/4 - 1/8 = 7/12
12) 13/18 - 29/45 + 8/15 = -1/2