8(1/2)-3(1/2)÷(2(1/2)+1(3/4))×2(3/7)=6(1/2)=6,5
1) 2(1/2)+1(3/4)=(5/2)+(7/4)=((5×2)+7)/4=17/4;
2) 3(1/2)÷(17/4)=(7/2)÷(17/4)=(7×4)/(2×17)=(7×2×2)/(2×17)=14/17;
3) (14/17)×2(3/7)=(14/17)×(17/7)=(14×17)/(17×7)=(7×2×17)/(17×7)=2;
4) 8(1/2)-2=(17/2)-2=(17-(2×2))/2=(17-4)/2=13/2=6(1/2)=6,5.