( 7/4) ÷ ( 5/9)
(4/10) ( 6/8)
3/4 - 1/5
5/4+3/6
(8/10) ÷ ( 6/4)
( 3/5 ) ( 7/2)
7/4
11/20
63/20
8/15
21/10
3/10