72*2.07-1.8*3.6和6.8*16.8+19.3*3.2

72*2.07-1.8*3.6和6.8*16.8+19.3*3.2


72*2.07-1.8*3.6 =3.6x20x2.07-1.8x3.6=3.6x(41.4-1.8)=3.6x(40-0.4)=3.6x40-3.6x0.4=144-1.44=142.566.8*16.8+19.3*3.2=6.8x16.8+(16.8+2.5)*3.2=6.8x16.8+16.8x3.2+2.5x3.2=16.8x(6.8+3.2)+2.5x4x0.8=16.8x10+10x0…



84又1/2÷14+16又1/2×1/14-(1-13/14)


84又1/2÷14+16又1/2×1/14-(1-13/14)
=84又1/2×1/14+16又1/2×1/14-1/14
=1/4×(84又1/2+16又1/2-1)
=1/4×100
=25



數學題():35=4/10=6÷()=2()/25=()%
大俠來,


(14):35=4/10=6÷(15)=(10)/25=(40)%
4/10=2/5=6/15=10/25=14/35