75%x（3/4-1/6)除7/8
=3/4*(3/4-1/6)*8/7
=6/7*(3/4-1/6)
=6/7*3/4-1/6*6/7
=9/14-1/7
=1/2
4/5+62.5除（3/4-1/2）
=4/5+62.5*1/(3/4-1/2）
=4/5+62.5*4
=4/5+250
=250.8
希望能够帮助你!*是什么意思*=×乘号