Question

13．直接寫出得數(shù)

1÷0.5=	$\frac{4}{7}$×3.5	102×45=	0.75-$\frac{3}{16}$=
9.8-4.8÷3=	99×40×0=	$\frac{4}{5}$×10÷$\frac{4}{5}$×10=	$\frac{1}{3}$+2÷3=

Answer 1

分析 根據(jù)小數(shù)、分?jǐn)?shù)和整數(shù)加減乘除法的計(jì)算方法進(jìn)行計(jì)算．
102×45根據(jù)乘法分配律進(jìn)行簡(jiǎn)算；
$\frac{4}{5}$×10÷$\frac{4}{5}$×10根據(jù)乘法交換律和結(jié)合律進(jìn)行簡(jiǎn)算．

解答 解：

1÷0.5=2	$\frac{4}{7}$×3.5=2	102×45=4590	0.75-$\frac{3}{16}$=$\frac{9}{16}$
9.8-4.8÷3=8.2	99×40×0=0	$\frac{4}{5}$×10÷$\frac{4}{5}$×10=100	$\frac{1}{3}$+2÷3=1

點(diǎn)評(píng) 口算時(shí)，注意運(yùn)算符號(hào)和數(shù)據(jù)，然后再進(jìn)一步計(jì)算．