1 口算
建议用时3分钟 评价：☆☆☆
$3 - \frac{1}{3} =$
$10 ÷ \frac{2}{5} =$
$0.75 ÷ \frac{3}{4} =$
$\frac{1}{3} × 4 ÷ 3 =$
$\frac{2}{7} × 21 =$
$\frac{3}{5} ÷ \frac{9}{10} =$
$\frac{3}{4} ÷ \frac{7}{8} =$
$18 × \frac{1}{3} - \frac{1}{3} =$
$12 × \frac{3}{4} =$
$\frac{5}{21} × 7 =$
$0.5 × \frac{3}{4} =$
$\frac{1}{6} + \frac{5}{6} × \frac{1}{5} =$
$\frac{1}{5} ÷ \frac{1}{4} =$
$\frac{5}{6} × 3.6 =$
$25.5 × 10\% =$
$( \frac{1}{2} + \frac{3}{5} ) × 10 =$

1. $2\frac{2}{3}$ 25 1 $\frac{4}{9}$ 6 $\frac{2}{3}$ $\frac{6}{7}$ $5\frac{2}{3}$ 9 $\frac{5}{3}$ $\frac{3}{8}$ $\frac{1}{3}$ $\frac{4}{5}$ 3 2.55 11

2 脱式计算（能简算的要简算）
建议用时6分钟 评价：☆☆☆
$(\frac{3}{5} + \frac{2}{7}) × 3.5$
$(\frac{1}{2} - \frac{3}{8}) ÷ \frac{3}{4}$
$\frac{3}{8} × 5 + \frac{3}{8} ÷ \frac{1}{2} + 37.5\%$
$27 ÷ \frac{5}{6} ÷ \frac{3}{10}$
$8.6 - \frac{5}{6} ÷ \frac{5}{12} × 60\%$
$\frac{11}{4} ÷ (\frac{2}{3} + \frac{1}{4}) × \frac{4}{5}$
$87 × \frac{3}{86}$
$3.7 × \frac{5}{6} + 2.3 ÷ \frac{6}{5}$
$20 ÷ [ (\frac{1}{8} + \frac{5}{6}) × \frac{6}{23} ]$

2. 3.1 $\frac{1}{6}$ 3 108 7.4 $\frac{12}{5}$ $3\frac{3}{86}$ 5 80

有26名阿姨在跳广场舞，她们中至少有（）人的属相相同；如果站成4列，总有一列至少有（）人。

3. 3 7