Question

15．計(jì)算，寫(xiě)出計(jì)算過(guò)程．
$\frac{1}{7}$÷$\frac{7}{8}$；           $\frac{3}{5}$×$\frac{15}{9}$；           $\frac{13}{40}$÷26；            $\frac{18}{49}$×$\frac{35}{54}$．

Answer 1

分析 根據(jù)分?jǐn)?shù)乘除法的計(jì)算法則計(jì)算即可．

解答 解：$\frac{1}{7}$÷$\frac{7}{8}$
=$\frac{1}{7}$×$\frac{8}{7}$
=$\frac{8}{49}$；         
 
$\frac{3}{5}$×$\frac{15}{9}$
=$\frac{3×15}{5×9}$
=1；          

$\frac{13}{40}$÷26
=$\frac{13}{40}$×$\frac{1}{26}$
=$\frac{1}{80}$；     
      
$\frac{18}{49}$×$\frac{35}{54}$
=$\frac{18×35}{49×54}$
=$\frac{5}{21}$．

點(diǎn)評(píng) 此題考查了分?jǐn)?shù)乘除法的計(jì)算法則的運(yùn)用．