Question

15．计算，写出计算过程．
$\frac{1}{7}$÷$\frac{7}{8}$；           $\frac{3}{5}$×$\frac{15}{9}$；           $\frac{13}{40}$÷26；            $\frac{18}{49}$×$\frac{35}{54}$．

Answer 1

分析 根据分数乘除法的计算法则计算即可．

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

点评 此题考查了分数乘除法的计算法则的运用．