2.5-75%x=八分之五2.5-0.75x=0.6250.75x=2.5-0.6250.75x=1.875x=1.875÷0.75x=2.5
2.5-75%x=八分之五0.75x=5/2-5/80.75x=15/8x=15/8*4/3x=5/2