分数乘除法简便运算怎么做（1）12又9/5*1

Question

如题所述

Answer 1

分数乘除法简便运算怎么做？
12又5/9×1又3/7+3又2/9×1又3/7-1又3/7×2又1/9-2/3×1又3/7
=12又5/9×10/7+3又2/9×10/7-10/7×2又1/9-2/3×10/7
=（12又5/9+3又2/9-2又1/9-2/3）×10/7
=10/7×13
=130/7

7.816×1.45+1.69×7.816+3.14×2.184
=7.816x(1.45+1.69)+3.14x2.184
=7.816x3.14+3.14x2.184
=3.14x(7.816+2.184)
=3.14x10
=31.4

6又1/9÷【7.125-2×（1-0.875）】
=55/9÷【7.125-2×0.125】
=55/9÷【7.125-0.25】
=55/9x8/55
=8/9
【1.1×20.83-（12.83-8）×1.1】÷（2/3+1/4)
=[1.1x(20.83-12.83)]÷(2/3+1/4)
=(1.1x8)÷(11/12)
=8.8x12/11
=0.8x12
=9.6
166又1/20÷41
=（164+41/20）÷41
=164÷41+41/20÷41
=4+1/20
=4又1/20

Answer 2

任何数乘1仍得原来的数。
12又9/5*1=12又9分之5