Question

18．直接寫(xiě)出得數(shù)

1÷0.1-1÷0.1=	9.99+8.99+7.99=	27.9×$\frac{2}{9}$=	$\frac{5}{6}$÷62.5%=
4÷$\frac{1}{5}$-$\frac{1}{4}$÷4	1-2+3-4-5=	（0.125-0.625）×$\frac{1}{8}$=	1000÷125÷8-1=

Answer 1

分析 根據(jù)四則運(yùn)算的計(jì)算法則計(jì)算即可求解．注意1÷0.1-1÷0.1，4÷$\frac{1}{5}$-$\frac{1}{4}$÷4先算除法再算減法，9.99+8.99+7.99變形為10-0.01+9-0.01+8-0.01，（0.125-0.625）×$\frac{1}{8}$根據(jù)乘法分配律計(jì)算，1000÷125÷8-1根據(jù)減法的性質(zhì)計(jì)算．

解答 解：

1÷0.1-1÷0.1=0	9.99+8.99+7.99=26.97	27.9×$\frac{2}{9}$=6.2	$\frac{5}{6}$÷62.5%=1$\frac{1}{3}$
4÷$\frac{1}{5}$-$\frac{1}{4}$÷4=19$\frac{15}{16}$	1-2+3-4-5=-7	（0.125-0.625）×$\frac{1}{8}$=-$\frac{1}{16}$	1000÷125÷8-1=0

點(diǎn)評(píng) 考查了運(yùn)算定律與簡(jiǎn)便運(yùn)算，四則混合運(yùn)算．注意運(yùn)算順序和運(yùn)算法則，靈活運(yùn)用所學(xué)的運(yùn)算定律簡(jiǎn)便計(jì)算．