70%x+20%x=3.6
90%x=3.6
x=3.6÷90%
x=4
x×3/5=20×1/4
x×3/5=5
x=5÷3/5
x=25/3
25+10x=4/5
10x=0.8-25
x=-24.2÷10
x=-2.42
x-15%x=68
75%x=68
x=68÷75%
x= 272/3
x+3/8x=121
11/8x=121
x=121÷11/8
x=88
5x-3×5/21=5/7
5x-5/7=5/7
5x=10/7
x=10/7÷5
x=2/7
2/3x÷1/4=12
2/3x=12×1/4
2/3x=3
x=3÷2/3
x=4.5
6x+5=13.4
6x=13.4-5
6x=8.4
x=8.4÷6
x=1.4
4x-6=38
4x=38+6
4x=44
x=11
x-0.8x=16+6
0.2x=22
x=22÷0.2
x=110
20x-8.5=1.5
20x=1.5+8.5
20x=10
x=0.5
x+25%x=90
125%x=90
x=90÷125%
x=720
4x-3×9=29
4x-27=29
4x=27+29
4x=56
x=56÷4
x=14
x-0.25x=6
0.75x=6
x=6÷0.75
x=8
4/5x-4=21
4/5x=21+4
4/5x=25
x=25÷4/5
x=31.25
4x-6=38
4x=38+6
4x=44
x=11
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