脱式计算,能简算的要简算(要列式)12*5/117.6*2又1/4+7又3/5*7又3/4(0.75÷3-0.2)*(1-4/5)解方程60%x-35%x=25

来源:学生作业帮助网 编辑:作业帮 时间:2024/05/04 04:47:01
脱式计算,能简算的要简算(要列式)12*5/117.6*2又1/4+7又3/5*7又3/4(0.75÷3-0.2)*(1-4/5)解方程60%x-35%x=25

脱式计算,能简算的要简算(要列式)12*5/117.6*2又1/4+7又3/5*7又3/4(0.75÷3-0.2)*(1-4/5)解方程60%x-35%x=25
脱式计算,能简算的要简算(要列式)
12*5/11
7.6*2又1/4+7又3/5*7又3/4
(0.75÷3-0.2)*(1-4/5)
解方程
60%x-35%x=25

脱式计算,能简算的要简算(要列式)12*5/117.6*2又1/4+7又3/5*7又3/4(0.75÷3-0.2)*(1-4/5)解方程60%x-35%x=25
12×5/11 = 60/11
7.6×(2×1/4)+ 7×3/5 -7×3/4
= 7.6/2 + 7×(3/5-3/4)
= 3.8 + 7×(-3/20)
= 19/5 - 21/20
=(19×4 -21 )/20
= 55/20
= 11/4 =2又3/4
(0.75÷3-0.2)×(1-4/5)
= (0.25-0.2)× (1/5) 注:0.25 - 0.2 = 0.05 = 5/100 = 1/20
=( 1/20) × (1/5)
=1/100 =0.01
60%x - 35%x = 25
25%x = 25
x = 100