一、口算。
$2.4\div0.16=$ $4.5 - 120\%=$ $\frac{4}{9}-\frac{1}{3}=$
$10.5\times40=$ $9\div0.18=$ $\frac{3}{8}\div\frac{5}{6}=$
$\frac{3}{16}\times\frac{4}{15}=$ $4.8 + 6.2=$ $\frac{7}{8}+\frac{1}{4}=$
$2.95 - 1.16=$ $3.4\div0.04=$ $\frac{4}{21}\times\frac{9}{5}=$
$4.5 + 2.69=$ $0.38 - 0.35=$ $\frac{2}{13}\div\frac{1}{26}=$
$0.84\times500=$ $18.84\div3.14=$ $\frac{3}{5}+\frac{1}{3}=$
$2.1\div0.07=$ $86\% - 36\%=$ $\frac{5}{8}\div\frac{5}{3}=$
$9.5\times10\%=$ $8.5 + 0.15=$ $\frac{3}{5}\times\frac{5}{18}=$
$\frac{8}{9}-\frac{7}{15}=$ $3.14\div6.28=$ $\frac{5}{7}-\frac{5}{14}=$
$150\times50\%=$ $10\div10\%=$ $\frac{3}{4}\times\frac{8}{11}=$

15 3.3 $\frac{1}{9}$
420 50 $\frac{9}{20}$
$\frac{1}{20}$ 11 $\frac{9}{8}$
1.79 85 $\frac{12}{35}$
7.19 0.03 4
420 6 $\frac{14}{15}$
30 50% $\frac{3}{8}$
0.95 8.65 $\frac{1}{6}$
$\frac{19}{45}$ 0.5 $\frac{5}{14}$
75 100 $\frac{6}{11}$

二、解方程或比例。
$\frac{8}{x}=\frac{2}{3}$ $0.36\times5 + 4x = 7.8$ $\frac{3}{4}x-\frac{1}{2}=\frac{1}{6}$

$x = 12$ $x = 1.5$ $x = \frac{8}{9}$