ewbch
幼苗
共回答了16个问题采纳率:100% 举报
51又2/3*3/5+41又1/3*3/4+31又1/2*2/3
=(50+1+2/3)*3/5+(40+1+1/3)*3/4+(30+1+1/2)*2/3
=50*3/5+3/5+2/3*3/5+40*3/4+3/4+1/3*3/4+30*2/3+2/3+1/2*2/3
=30+(3/5+2/5)+30+(3/4+1/4)+20+(2/3+1/3)
=30+1+30+1+20+1
=83
8/17*2/23+2/17*9/23
=2/17*4*2/23+2/17*9/23
=2/17*(4*2/23+9/23)
=2/17*17/23
=2/23
1年前
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