25*6.4*12.5 (3-1/4-5/12)÷2/3 3.25*5.8+67.5*0.58 5/7÷(7-6*2/3)怎样简便就怎样算

问题描述:

25*6.4*12.5 (3-1/4-5/12)÷2/3 3.25*5.8+67.5*0.58 5/7÷(7-6*2/3)
怎样简便就怎样算

25*6.4*12.5=(25x4x4)x(0.8x12.5)=400x10=4000 (3-1/4-5/12)÷2/3 =3x3/2-1/4x3/2-5/12x3/2=9/2-3/8-5/8=9/2-1=7/23.25*5.8+67.5*0.58 =(3.25+6.75)x5.8=10x5.8=585/7÷(7-6*2/3)=5/7÷(7-4)=5/7÷3=5/21请好...