前辈帮我做一些简便计算题.一个小时后就要.

3个回答

  • ①38×37分之19

    =(37+1)×19/37……变一变,就简便

    =37×19/37+19/37

    =19+19/37

    19又19/37

    ②29×30分之13

    =(30-1)×13/30

    =30×13/30-13/30

    =13-13/30

    =12又17/30

    ③800÷25

    =(800×4)÷(25×4)……商不变的性质

    =3200÷100

    =32

    ④16÷0.125

    =(16×8)÷(0.125×8)……商不变的性质

    =128÷1

    =128

    ⑤0.75×18÷0.15

    =(0.75÷0.15)×18

    =5×18

    =90

    ⑥4.8×0.25

    =1.2×(4×0.25)……变一变,就简便

    =1.2×1

    =1.2