51又2/3除以5/3加上71又3/4除以7/4加上91又4/5除以9/5,怎么简算?

问题描述:

51又2/3除以5/3加上71又3/4除以7/4加上91又4/5除以9/5,怎么简算?

(51+2/3)÷(5/3)+(71+3/4)÷(7/4)+(91+4/5)÷(9/5)=(50+5/3)*(3/5)+(70+7/4)*(4/7)+(90+9/5)*(5/9)=50*3/5+(5/3)(3/5)+70*4/7+(7/4)*(4/7)+90*5/9+(9/5)*(5/9)=30+1+40+1+50+1=123