Question

19．直接寫出得數(shù)．

7÷0.01=	16×25=	45÷1.25÷8=	2.5-0.36-0.64=
1÷$\frac{1}{7}$×$\frac{1}{7}$=	$\frac{3}{8}$×$\frac{5}{7}$÷$\frac{3}{8}$×$\frac{5}{7}$=	2.2×99+2.2=	24×5=
0.42-0.22=	$\frac{1}{4}$：125%=	1×0.2÷0.2+0.2=	45.6-6.85+4.4=

Answer 1

分析 根據(jù)四則運(yùn)算的計(jì)算法則進(jìn)行計(jì)算即可求解．注意16×25變形為4×（4×25）計(jì)算，45÷1.25÷8根據(jù)除法的性質(zhì)計(jì)算，2.5-0.36-0.64根據(jù)減法的性質(zhì)計(jì)算，$\frac{3}{8}$×$\frac{5}{7}$÷$\frac{3}{8}$×$\frac{5}{7}$變形為（$\frac{3}{8}$÷$\frac{3}{8}$）×（$\frac{5}{7}$×$\frac{5}{7}$）計(jì)算，2.2×99+2.2根據(jù)乘法分配律計(jì)算，45.6-6.85+4.4變形為45.6+4.4-6.85計(jì)算．

解答 解：

7÷0.01=700	16×25=400	45÷1.25÷8=4.5	2.5-0.36-0.64=1.5
1÷$\frac{1}{7}$×$\frac{1}{7}$=1	$\frac{3}{8}$×$\frac{5}{7}$÷$\frac{3}{8}$×$\frac{5}{7}$=$\frac{25}{49}$	2.2×99+2.2=220	24×5=120
0.42-0.22=0.12	$\frac{1}{4}$：125%=$\frac{1}{5}$	1×0.2÷0.2+0.2=1.2	45.6-6.85+4.4=43.15

點(diǎn)評(píng) 考查了四則運(yùn)算，關(guān)鍵是熟練掌握計(jì)算法則正確進(jìn)行計(jì)算．