Question

7．計(jì)算
$\frac{2}{3}$×$\frac{3}{5}$÷$\frac{9}{25}$
$\frac{84}{169}$×13÷$8\frac{2}{5}$
42÷$\frac{7}{8}$÷$\frac{3}{4}$．

Answer 1

分析 根據(jù)分?jǐn)?shù)乘除法的運(yùn)算法則計(jì)算，除法要先變成乘法在計(jì)算．

解答 解：①$\frac{2}{3}$×$\frac{3}{5}$÷$\frac{9}{25}$
=$\frac{2}{3}$×$\frac{3}{5}$×$\frac{25}{9}$
=$\frac{10}{9}$

②$\frac{84}{169}$×13÷$8\frac{2}{5}$
=$\frac{84}{169}$×13×$\frac{5}{42}$
=$\frac{10}{13}$

③42÷$\frac{7}{8}$÷$\frac{3}{4}$
=42×$\frac{8}{7}$×$\frac{4}{3}$
=64

點(diǎn)評(píng) 此題考查分?jǐn)?shù)乘除法運(yùn)算順序，認(rèn)真分析數(shù)據(jù)找到正確的計(jì)算方法．