1/12+1/15+1/10
1/12+1/15+1/10
1÷(1/10+1/15+1/12)
1/10*11+1/11*12+1/12*13+1/13*14+1/14*15等于?
2/1 3/1 4/1 5/1 6/1 8/1 10/1 12/1 15/1 20/1
(1/10+1/12+1/15)*(6-x)+(1/12+1/15)*x=1怎么解啊!
计算:1/9*10+1/10*11+1/11*12+1/12*13+1/13*14+1/14*15+1/15*16+1/
(1/2+1/4+1/6+1/10+1/12+1/60)/(1+1/3+1/5+1/10+1/15+1/30)
(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)
A=1\10+1\11+1\12+1\13+1\+1\14+1\15+1\16+1\17+1\18+1\19分之1 求A
(1+1/3+1/5+1/10+1/15+1/30)/(1/2+1/4+1/6+1/12+1/20+1/60)=R
将1/5+1/6++1/8+1/9+1/10+1/11+1/12+1/13+1/14+1/15+1/16+1/17的计算
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)=?