1.4*0.8*2.5*12.5
=(4*2.5)*(0.8*12.5)
=10*10
=100
2.0.65*14+87*65%-13/20
=0.65*14+0.65*87-0.65
=0.65*(14+87-1)
=0.65*100
=65
3.x-3/4x=二又5/8
1/4x=21/8
x=21/2=10.5
1.4*0.8*2.5*12.5
=(4*2.5)*(0.8*12.5)
=10*10
=100
2.0.65*14+87*65%-13/20
=0.65*14+0.65*87-0.65
=0.65*(14+87-1)
=0.65*100
=65
3.x-3/4x=二又5/8
1/4x=21/8
x=21/2=10.5