1.234*100-(234+766)=22400
2.(5/3+11/4+19/5)/(2*5/3+2*11/4+2*19/5)=1/2
3.88/10/[87+5/8*(1+3/5)]=88/10/[87+(5/8)*(8/5)]=88/10/88=1/10
4.(10/43+33/43)*11/1993=11/1993
5.(988.2/988.2)/(292.4/292.4)*1998.8/1999.8=1998.8/1999.8
6.(42+1/5+1/6)*1/7-1/7*(1/5+1/6)=42*1/7=6