Question

3．直接寫(xiě)出得數(shù)．

$\frac{5}{6}-\frac{1}{6}$=	$\frac{3}{10}+\frac{1}{5}$=	$\frac{1}{2}-\frac{1}{8}$=	$\frac{1}{5}-\frac{2}{8}+\frac{4}{5}$=
$\frac{1}{3}+\frac{1}{5}$=	$\frac{1}{5}-\frac{1}{7}$=	1-$\frac{1}{5}-\frac{4}{5}$=	$\frac{1}{6}+\frac{1}{5}+\frac{5}{6}$=

Answer 1

分析 同分母分?jǐn)?shù)相加減，分母不變，分子相加減．
異分母分?jǐn)?shù)相加減，先通分，變成同分母的分?jǐn)?shù)相加減，再計(jì)算；
$\frac{1}{6}+\frac{1}{5}+\frac{5}{6}$、$\frac{1}{5}-\frac{2}{8}+\frac{4}{5}$根據(jù)加法交換律簡(jiǎn)算．

解答 解：

$\frac{5}{6}-\frac{1}{6}$=$\frac{2}{3}$	$\frac{3}{10}+\frac{1}{5}$=$\frac{1}{2}$	$\frac{1}{2}-\frac{1}{8}$=$\frac{3}{8}$	$\frac{1}{5}-\frac{2}{8}+\frac{4}{5}$=$\frac{3}{4}$
$\frac{1}{3}+\frac{1}{5}$=$\frac{8}{15}$	$\frac{1}{5}-\frac{1}{7}$=$\frac{2}{35}$	1-$\frac{1}{5}-\frac{4}{5}$=0	$\frac{1}{6}+\frac{1}{5}+\frac{5}{6}$=1$\frac{1}{5}$

點(diǎn)評(píng) 本題考查了簡(jiǎn)單的運(yùn)算，要注意根據(jù)運(yùn)算法則和運(yùn)算定律快速準(zhǔn)確的得出答案．