1. 脱式计算。（能简算的要简算）
$4.67-(2.98+0.67)$ $46×\frac {44}{45}$
$20×(\frac {4}{5}+\frac {7}{10}-\frac {3}{4})$ $30÷(\frac {3}{4}-\frac {3}{8})$
$2008×\frac {2007}{2009}$ $2\frac {1}{6}-2.86×(6.25-6\frac {1}{4})$
$4÷1\frac {2}{3}+6×\frac {3}{5}$ $4.85×0.17+0.485×8.3$
$(0.86+0.86+0.86+0.86)×25$ $1-\frac {7}{9}÷\frac {7}{8}$

$4.67-(2.98+0.67)$
$=4.67-0.67-2.98$
$=4-2.98$
$=1.02$
$46×\frac{44}{45}$
$=(45+1)×\frac{44}{45}$
$=45×\frac{44}{45}+1×\frac{44}{45}$
$=44+\frac{44}{45}$
$=44\frac{44}{45}$
$20×(\frac{4}{5}+\frac{7}{10}-\frac{3}{4})$
$=20×\frac{4}{5}+20×\frac{7}{10}-20×\frac{3}{4}$
$=16+14-15$
$=30-15$
$=15$
$30÷(\frac{3}{4}-\frac{3}{8})$
$=30÷(\frac{6}{8}-\frac{3}{8})$
$=30÷\frac{3}{8}$
$=30×\frac{8}{3}$
$=80$
$2008×\frac{2007}{2009}$
$=(2009-1)×\frac{2007}{2009}$
$=2009×\frac{2007}{2009}-1×\frac{2007}{2009}$
$=2007-\frac{2007}{2009}$
$=2006\frac{2}{2009}$
$2\frac{1}{6}-2.86×(6.25-6\frac{1}{4})$
$=2\frac{1}{6}-2.86×(6.25-6.25)$
$=2\frac{1}{6}-2.86×0$
$=2\frac{1}{6}-0$
$=2\frac{1}{6}$
$4÷1\frac{2}{3}+6×\frac{3}{5}$
$=4÷\frac{5}{3}+6×\frac{3}{5}$
$=4×\frac{3}{5}+6×\frac{3}{5}$
$=(4+6)×\frac{3}{5}$
$=10×\frac{3}{5}$
$=6$
$4.85×0.17+0.485×8.3$
$=4.85×0.17+4.85×0.83$
$=4.85×(0.17+0.83)$
$=4.85×1$
$=4.85$
$(0.86+0.86+0.86+0.86)×25$
$=0.86×4×25$
$=0.86×(4×25)$
$=0.86×100$
$=86$
$1-\frac{7}{9}÷\frac{7}{8}$
$=1-\frac{7}{9}×\frac{8}{7}$
$=1-\frac{8}{9}$
$=\frac{1}{9}$

2. 解方程。
$4x-2.5×4=1.5$ $x+\frac {5}{6}x=1540$

第一个方程：
解：4x - 2.5×4 = 1.5
4x - 10 = 1.5
4x = 1.5 + 10
4x = 11.5
x = 11.5 ÷ 4
x = 2.875（或$x=\frac{23}{8}$）
第二个方程：
解：$x + \frac{5}{6}x = 1540$
$(1 + \frac{5}{6})x = 1540$
$\frac{11}{6}x = 1540$
$x = 1540 × \frac{6}{11}$
$x = 840$