1/3*2/5+1/6*1/5+1/12*3/10

2/1 3/1 4/1 5/1 6/1 8/1 10/1 12/1 15/1 20/1 找规律 3/1 6/3 9/6 12/10 ( ) ( ) 5/4 5/2 5/1 10/1 ( ) ( ) (1/2+1/3+1/4+1/5+1/6+1/7+1/8+1/9+1/10+1/11+1/12+1/13+1/14+1/ (1/2+1/4+1/6+1/10+1/12+1/60)/(1+1/3+1/5+1/10+1/15+1/30) (-12)*(-1/2+2/3-5/6) 1 1 1 1 2 1 1 3 3 1 1 4 6 4 1 1 5 10 10 5 1 1 6 15 20 15 6 1 (1+1/3+1/5+1/10+1/15+1/30)/(1/2+1/4+1/6+1/12+1/20+1/60)(用简算) (1+1/3+1/5+1/10+1/15+1/30)/(1/2+1/4+1/6+1/12+1/20+1/60)=R 简算:（1+1/3+1/5+1/10+1/15+1/30）÷（1/2+1/4+1/6+1/12+1/20+1/60）＝? （1+1/3+1/5+1/10+1/15+1/30）÷（1/2+1/4+1/6+1/12+1/20+1/60） 拖式：4/5*(-25/3)*(-7/10)= (7/12-5/6+1)*(-24)= [1/5+(-1/2)+(-5/ 1/2+1/3+1/4+1/5+1/6+1/7+1/8+1/9+1/10+1/11+1/12的整数部分是几,为啥