原式=26+8/9+11+9/11-2-2/11+5+2/3-1/6+13+5/9 =(26+11-2+5+13)+(8/9+9/11-2/11+2/3-1/6+5/9) =53+9/11+11/9+1/2 =53+1+9/11+2/9+1/2 =54+1+107/198 =55又107/198
