百分之32X+40=百分之80X解：80%x-32%x=400.48x=40x=40÷0.48x=250/3
32%X+40=80%X80%X-32%X=4048%X=40X=40÷48%X=250/3
0.32x+40=0.8x0.32x-0.8x=-40-0.48x=-40x=25/4
