Question

8．计算下面各题．

42×$\frac{9}{28}$	$\frac{9}{44}$×11	$\frac{23}{24}$×$\frac{8}{69}$
$\frac{5}{4}$×$\frac{1}{8}$×16	$\frac{9}{10}$×$\frac{2}{3}$×$\frac{5}{6}$	$\frac{30}{49}$×15×$\frac{7}{25}$

Answer 1

分析 根据分数乘法运算的计算法则计算即可求解，注意先约分再计算．

解答 解：42×$\frac{9}{28}$=13$\frac{1}{2}$

$\frac{9}{44}$×11=$\frac{9}{4}$         

$\frac{23}{24}$×$\frac{8}{69}$=$\frac{1}{9}$

$\frac{5}{4}$×$\frac{1}{8}$×16
=$\frac{5}{32}$×16
=2$\frac{1}{2}$        

 $\frac{9}{10}$×$\frac{2}{3}$×$\frac{5}{6}$
=$\frac{3}{5}$×$\frac{5}{6}$     
=$\frac{1}{2}$     

 $\frac{30}{49}$×15×$\frac{7}{25}$
=$\frac{450}{49}$×$\frac{7}{25}$
=$\frac{18}{7}$

点评 考查了分数乘法运算，关键是熟练掌握计算法则正确进行计算．