4.8÷8＋5.2×8分之1
=4.8x1/8+5.2x1/8
=(4.8+5.2)x1/8
=10x1/8
=5/4
（2分之1－3分之1×75％）除0.25
=(1/2-1/3x3/4)x4
=(1/2-1/4)x4
=1/4x4
=1