12比5多百分之140
(12-5)÷5x100%
=7/5x100%
=140%
5比20少百分之75.
(20-5)÷20x100%
=15÷20x100%
=75%
75的60%是（45 ）.
75x60%=45
（ 140）的30%是42
42÷30%=140