3/4x-5%x=17.5
3/4x-1/20x=35/2
15/20x=35/2
x=25
0.6x+2/5x-3/7x=1又1/3
3/5x+2/5x-3/7x=4/3
x-3/7x=4/3
4/7x=4/3
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