2a/3=4b/5a/b=(4/5)÷(2/3)=6/5即a:b=6:5=1.2
2a/3=4b/52a*5=4b*310a=12ba:b=12:10a:b=6:5注：*为乘号
=4/5:2/3=4/5×3/2=1.2
a:b＝4/5:2/3＝4/5×3/2＝6/5＝1.2
