11/2*5+11/5*8+11/11*14+11/14*17

问题描述:

11/2*5+11/5*8+11/11*14+11/14*17

11/2*5+11/5*8+11/11*14+11/14*17=11/3*(3/2*5+3/5*8+3/11*14+3/14*17)=11/3*(1/2-1/5+1/5-1/8+1/11-1/14+1/14-1/17)=11/3*(1/2-1/8+1/14-1/17)=11/3*(3/8 + 3/14*17)=11*(1/8 +1/238)=11*246/(8*238)=1353/...