$\frac{3}{4} × \frac{4}{5} =$
$\frac{17}{25} × 15 =$
$\frac{6}{5} × \frac{5}{7} × \frac{7}{6} =$
$0.36 × \frac{1}{4} =$
$\frac{8}{9} × \frac{3}{10} =$
$14 × \frac{7}{8} - 6 × \frac{7}{8} =$
$0.56 × \frac{1}{8} =$
$\frac{14}{15} × \frac{25}{21} =$
$\frac{3}{4} × \frac{4}{5} × 20 =$
$\frac{8}{15} × 2.5 =$
$\frac{12}{121} × \frac{11}{13} =$
$( \frac{1}{3} - \frac{1}{5} ) × \frac{5}{6} =$
$\frac{28}{39} × \frac{26}{7} =$
$\frac{19}{33} × \frac{11}{38} =$
$( \frac{1}{9} + \frac{1}{11} ) × 9 × 11 =$

1. $\frac{3}{5}$ $\frac{51}{5}$ 1
0.09 $\frac{4}{15}$ 7
0.07 $\frac{10}{9}$ 12
$\frac{4}{3}$ $\frac{12}{143}$ $\frac{1}{9}$
$\frac{8}{3}$ $\frac{1}{6}$ 20

2 脱式计算（能简算的要简算） 建议用时4分钟 评价：☆☆☆
$\frac{1}{6} + \frac{5}{6} × \frac{1}{6}$
$\frac{10}{39} × ( \frac{4}{5} + \frac{1}{2} )$
$( \frac{3}{4} + \frac{5}{8} ) × 4 × 8$
$49 × \frac{5}{48}$
$\frac{11}{14} × \frac{5}{6} + \frac{3}{14} × \frac{5}{6}$
$( \frac{8}{9} + \frac{16}{17} ) × \frac{1}{8} + \frac{15}{17}$

2. $\frac{11}{36}$ $\frac{1}{3}$ 44
$5\frac{5}{48}$ $\frac{5}{6}$ $1\frac{1}{9}$

3 看图列式
建议用时2分钟 评价：☆☆☆
(1)
(2)

3. (1) $120×(1+\frac{1}{3})=160$(只)
(2) $120×\frac{1}{2}×\frac{1}{4}=15$(元)