12x+3/4x=5/8
解:51/4x=5/8
x=5/8除以51/4
x=5/102
1/5*2/3x=4/5
解:2/3x=4/5除以1/5
2/3x=4
x=4除以2/3
x=6
12X+3/4X=5/8
102/8X=5/8
X=5/102
x=5/102
x=6
12x+3/4x=5/8
(12+3/4)x=5/8
(51/4)x=5/8
x=5/8÷51/4
x=5/102