(1)
=6/5+6/1+9/7
=1+9/7
=1又9/7
(2)
=40/25-40/16+40/10
=40/19
(3)
=15/14-(15/10-15/3)
=15/7
(4)
=40/38+(40/32-40/63
=40/63
(5)
=30/25-(30/21-30/10)
=5/4
(6)
=24/33-(24/16-24/6)
=12/11
(7)
=8/17-(27/7-27/20)
=2又8/1-1
=1又8/1
(8)
=6-(11/3+11/8)
=6-1
=5

(9)
=11/18-11/7-8/3
=1-8/3
=8/5
(10）
=（9/7+9/2)+(10/3+10/11)
=1+2
=3
(11）
=（15/7+15/8)+（12/7-12/7)
=1+0
=1
(12)
=1又11/4-(8/3+8/5)
=1又11/4_1
=11/4
(13)
=14/4+(14/9+14/7)
=7/10
(14)
=12/-12/5+12/4
=3/2
(15)
=(6/5+6/1)-(10/3+10/7)
=1-1
=0
（16）
=36/28+36/9-36/12
=36/25
(17）
=9/5-9/5+5/1
=5/1
(18)
=24/21+24/8+24/18
=24/47
(19)
=5/6-5/1-10/3
=1-10/3
=10/7
(20)
=28/21-28/1-28/6
=2/1

二：
1.
5/1+8/3=30/23
1-40/23=40/7
2.
5/6-5/1=1
1-8/3=8/5
3.
3/5+6/5=1又10/1
1又10/1-1=10/1