小學生奧數(shù)分數(shù)簡算題練習

字號:

這篇關(guān)于小學生奧數(shù)分數(shù)簡算題練習,是特地為大家整理的,希望對大家有所幫助!
    1/2*3+1/3*4+1/4*5+……+1/49*50
    =(1/2-1/3)+(1/3-1/4)+(1/4-1/5)+……+(1/49-1/50)
    =1/2-1/3+1/3-1/4+1/4-1/5+……+1/49-1/50
    =1/2-1/50
    =12/25
    1/1*3+1/3*5+1/5*7+……+1/47*49
    =1/2*[(1-1/3)+(1/3-1/5)+(1/5-1/7)+……+(1/47-1/49)]
    =1/2*(1-1/3+1/3-1/5+1/5-1/7+……+1/47-1/49)
    =1/2*(1-1/49)
    =1/2*48/49
    =24/49
    1-1/6+1/42+1/56+1/72
    =1-1/6+1/6-1/7+1/7-1/8+1/8-1/9
    =1-1/9
    =8/9