12.75 :1.252分之7 :7分之30 急

问题描述:

12.75 :1.25
2分之7 :7分之30

12.75 :1.25
=12.75*4:1.25*4
=51:5
=51/5
=10.2
2分之7 :7分之30
=2分之7*14 :7分之30*14
=49:60
=49/60