一、直接写出得数。（共 32 分）
$4 - 3.25 =$ $4.14 + 3.86 =$ $1.8 + 0.25 =$ $3.6 ÷ 8 × 0.2 =$
$0.32 × 0.2 =$ $3.5 + 7.6 =$ $2.21 - 0.2 =$ $2.5 × 0.8 × 4 =$
$2.58 + 3.12 =$ $0.3 × 0.2 =$ $7.6 ÷ 1.9 =$ $2 × 3.14 × 0.8 =$
$3.5 ÷ 0.35 =$ $5.2 - 1.8 =$ $0.35 × 200 =$ $12 ÷ 1.2 + 8.6 =$
$4.8 ÷ 96 =$ $40 ÷ 0.08 =$ $0.8 × 1.4 =$ $4.56 - 0.5 - 1.5 =$
$\frac{5}{9} - \frac{2}{45} =$ $\frac{21}{10} + \frac{3}{10} =$ $\frac{13}{15} + \frac{4}{5} =$ $\frac{6}{7} × \frac{1}{2} × \frac{1}{3} =$
$\frac{3}{10} + \frac{1}{2} =$ $\frac{5}{24} × 32 =$ $\frac{4}{5} × \frac{20}{11} =$ $\frac{13}{8} - \frac{1}{2} + \frac{5}{8} =$
$\frac{5}{6} - \frac{3}{4} =$ $\frac{2}{15} × 45 =$ $\frac{1}{4} + \frac{1}{5} =$ $\frac{17}{6} - \frac{5}{6} + \frac{2}{3} =$

一 0.75 8 2.05 0.09 0.064 11.1 2.01 8 5.7 0.06 4 5.024 10 3.4 70 18.6 0.05 500 1.12 2.56 $\frac{23}{45}$ $\frac{12}{5}$ $\frac{5}{3}$ $\frac{1}{7}$ $\frac{4}{5}$ $\frac{20}{3}$ $\frac{16}{11}$ $\frac{7}{4}$ $\frac{1}{12}$ 6 $\frac{9}{20}$ $2\frac{2}{3}$

二、计算下面各题，能简算的要简算。（共 24 分）
$\frac{15}{8} - (\frac{8}{15} + \frac{7}{8})$ $\frac{13}{9} - \frac{1}{3} + \frac{2}{3}$ $\frac{5}{9} × \frac{9}{4} × \frac{12}{5}$
$\frac{5}{9} - \frac{5}{12} + \frac{7}{12} + \frac{4}{9}$ $5 - \frac{3}{8} - \frac{5}{9} - \frac{5}{8}$ $27.5 × 3.7 - 7.5 × 3.7$

二 $\frac{7}{15}$ $\frac{16}{9}$ 3 $1\frac{1}{6}$ $3\frac{4}{9}$ 74

三、解方程。（共 24 分）
$0.4 + 2x = 10$ $5x - 0.25 × 5 = 8$ $x + \frac{2}{7} - \frac{1}{3} = \frac{3}{5}$
$2.5(x - 1.6) = 4.8$ $2.9x + 1.5x = 19.8$ $\frac{5}{6} + \frac{17}{42} - x = \frac{1}{14}$

三 $x = 4.8$ $x = 1.85$ $x = \frac{68}{105}$ $x = 3.52$ $x = 4.5$ $x = \frac{7}{6}$