化简比 (1)90:60:30 (2)3/2:5/4:15/7 (3)2.5:0.75:4.5 (
问题描述：
化简比 (1)90:60:30 (2)3/2:5/4:15/7 (3)2.5:0.75:4.5 (
化简比
(1)90:60:30
(2)3/2:5/4:15/7
(3)2.5:0.75:4.5
(4)8/7:2.1:1又2/1
已知a:b等于5:9,a:c等于4:9求a:b:c
已知a:b等于2/1:3/1,b:c等于0.3:0.2
答
=(1)3:2:1(2)42:35:60(3)50:17:90(4)80:147:105(5)a:b:c=20:36:45(6)a:b:c=2:3:2