=(0.75+4分之1)+(8分之5+0.125)=1+(0.625+0.125)=1+0.75=1.75
=3/4+5/8+1/4+1/8=6/8+5/8+2/8+1/8=14/8=1.75
=3/4+1/4+5/8+1/8=1+6/8=7/4
后三项全划成八分之几