75*0.82+2.5*8.2
=75*0.82+25*0.82
=0.82（75+25）
=82
13.75+45÷1.8*25
=13.75+45÷45
=13.75+1
=14.75
12.5*4.8÷1.5÷5
=12.5*8*0.6÷1.5÷5
=60÷5÷1.5
=12÷1.5
=8