42.41加34.5除(14.75减12.25)简便算法 18减1.8除0.125除0.8简便算法 22.6减5.4乘0

42.41+34.5÷（14.75-12.25）
=42.41+34.5÷2.5
=42.41+13.8
=56.21
18-1.8÷0.125÷0.8
=18-1.8÷（0.125*0.8）
=18-1.8÷0.1
=18-18
=0
22.6-5.4*0.4-1.28
=22.6-2.16-1.28
=19.16
5.4÷1.5+3.6÷4
=3.6+0.9
=4.5