(-3/4-5/6+7/8)*(-24)
=-3/4*(-24)-5/6*(-24)+7/8*(-24)
=18+20-21
=17
(-3/5)*3/5+8/25*(-24)
=-9/25-8*24/25
=-3*3/25-64*3/25
=(-3-64)*3/25
=-67*3/25
=-201/25
=-8又1/25
(2*3*4*5 )*(1/2+1/3+1/4+1/5)
=(2*3*4*5 )*1/2+(2*3*4*5 )*1/3+(2*3*4*5 )*1/4+(2*3*4*5 )*1/5
=3*4*5+2*4*5+2*3*5+2*3*4
=60+40+30+24
=154
(-3/4-5/6+7/8)*(-24)=(1/8-5/6)*(-24)=-3+20=17
(-3/5)*3/5+8/25*(-24)=1/25*(-9-8*24)=-201/25
(2*3*4*5 )*(1/2+1/3+1/4+1/5)=3*4*5+2*4*5+2*3*5+2*3*4=60+40+30+24=154
简便运算:
(-3/4-5/6+7/8)*(-24)
=-3/4*(-24)-5/6*(-24)+7/8*(-24)
=18+20-21
=17
(-3/5)*3/5+8/25*(-24)
=-9/25-8*24/25
=-3*3/25-64*3/25
=(-3-64)*3/25
=-67*3/25
=-201/25
(2*3*4*5 )*(1/2+1/3+1/4+1/5)
=(2*3*4*5 )*1/2+(2*3*4*5 )*1/3+(2*3*4*5 )*1/4+(2*3*4*5 )*1/5
=3*4*5+2*4*5+2*3*5+2*3*4
=60+40+30+24
=154
(-3/4-5/6+7/8)*(-24)
=-3/4*(-24)-5/6*(-24)+7/8*(-24)
=18+20-21
=17
(-3/5)*3/5+8/25*(-24)
=-9/25-8*24/25
=-3*3/25-64*3/25
=(-3-64)*3/25
=-67*3/25
=-201/25
=-8又1/25
``````````````
(2*3*4*5 )*(1/2+1/3+1/4+1/5)
=(2*3*4*5 )*1/2+(2*3*4*5 )*1/3+(2*3*4*5 )*1/4+(2*3*4*5 )*1/5
=3*4*5+2*4*5+2*3*5+2*3*4
=60+40+30+24
=154
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