大家帮帮忙，请把以下题的过程帮忙写出来

来源：百度知道 编辑：UC知道 时间：2024/05/03 14:50:36
(3.1+4.2)-(4.2-1.9)

(-7/1)-(-7/2)-1又7/3

-1-(+3又3/1)-(-1又3/2)

(-8)+(-2)-(-3又2/1)-(+4)

(-10)╳(+3)╳(-2/1)╳(-5又3/1)╳(+5/4)

16╳(-18)╳0.25╳(-100)

(-12/5)╳15/8╳(-1又2/1)╳3/2
就是这些题，谢谢大家了

(3.1+4.2)-(4.2-1.9)
=3.1+1.9+4.2-4.2
=5

(-7/1)-(-7/2)-1又7/3
=-42/6+21/6-20/6
=-41/6
=-6又5/6

-1-(+3又3/1)-(-1又3/2)
=-1-6+2.5
=-4.5

(-8)+(-2)-(-3又2/1)-(+4)
=-10+5-4
=-9

(-10)╳(+3)╳(-2/1)╳(-5又3/1)╳(+5/4)
=-30╳(-2)╳(-8)╳(5/4)
=60╳(-10)
=-600

16╳(-18)╳0.25╳(-100)
=16╳(-18)╳1/4╳(-100)
=1800╳4
=7200

(-12/5)╳15/8╳(-1又2/1)╳3/2
=(-12/5)╳15/8╳(-3)╳3/2
=81/4
=20.25