一、口算。
$\frac{1}{3}×1.4=$
$\frac{1}{2}×\frac{5}{8}=$
$\frac{9}{10}×\frac{30}{7}=$
$0.26×\frac{10}{13}=$
$33×\frac{4}{11}=$
$\frac{1}{3}×\frac{1}{3}=$
$\frac{2}{3}×\frac{1}{9}=$
$0.3×\frac{1}{9}=$
$\frac{17}{28}×7=$
$\frac{3}{8}×0.4=$
$\frac{9}{4}×\frac{1}{27}=$
$4.5×\frac{8}{15}=$
$\frac{2}{3}×2.1=$
$4.2×\frac{2}{7}=$
$\frac{23}{7}×\frac{63}{46}=$
$\frac{8}{9}×\frac{3}{8}=$
$\frac{2}{5}×2.5=$
$\frac{3}{7}×0.6=$
$\frac{1}{3}×99=$
$\frac{9}{10}×\frac{5}{9}=$
$\frac{6}{7}×\frac{2}{3}=$

1.$\frac{7}{15}$ 2.$\frac{5}{16}$ 3.$\frac{27}{7}$ 4.$\frac{1}{5}$ 5.$12$ 6.$\frac{1}{9}$ 7.$\frac{2}{27}$ 8.$\frac{1}{30}$ 9.$\frac{17}{4}$ 10.$\frac{3}{20}$ 11.$\frac{1}{12}$ 12.$\frac{12}{5}$ 13.$\frac{7}{5}$ 14.$\frac{6}{5}$ 15.$\frac{9}{2}$ 16.$\frac{1}{3}$ 17.$1$ 18.$\frac{9}{35}$ 19.$33$ 20.$\frac{1}{2}$ 21.$\frac{4}{7}$

二、计算下面各题，能用简便算法的就用简便算法。
$16×\frac{9}{8}×\frac{5}{9}$
$7×(\frac{6}{7}-\frac{5}{14})$
$\frac{7}{11}×\frac{11}{10}-\frac{7}{11}×0.1$
$\frac{6}{25}×24$
$\frac{9}{10}×2.3+\frac{9}{10}×7.7$
$\frac{2}{15}×\frac{5}{4}+\frac{5}{27}×\frac{3}{4}$

1.$10$ 2.$\frac{7}{2}$ 3.$\frac{7}{11}$ 4.$5\frac{19}{25}$ 5.$9$ 6.$\frac{11}{36}$