识别出错

1 12 $\frac{3}{4}$
$\frac{1}{2}$ $\frac{4}{5}$ $\frac{10}{9}$ $\frac{1}{16}$
$\frac{1}{6}$ $\frac{6}{5}$ 5 $\frac{3}{13}$
$\frac{5}{8}$ $\frac{1}{4}$ 1 $\frac{1}{24}$
3 1 $\frac{21}{2}$ $\frac{3}{2}$

2.计算下面各题,能简算的要简算。(每题3★)
$\frac{13}{19} - \frac{3}{8} + \frac{6}{19}$
$\frac{8}{13} - (\frac{5}{11} - \frac{5}{13})$
$\frac{8}{9} - \frac{3}{11} + \frac{10}{9} - \frac{7}{11}$
$\frac{3}{8} + \frac{5}{4} - \frac{1}{2}$
$10 - \frac{5}{13} - \frac{9}{13} - \frac{12}{13}$
$\frac{6}{11} + \frac{11}{15} + \frac{5}{11} + \frac{4}{15}$

$\frac{5}{8}$
$\frac{6}{11}$
$1\frac{1}{11}$
$\frac{9}{8}$
8
2

3.解方程。（每题3★）
$x-\dfrac{5}{8}=\dfrac{7}{12}$
$\dfrac{5}{8}x=1$
$x-\dfrac{6}{7}=\dfrac{5}{8}-\dfrac{1}{2}$

$x=\frac{29}{24}$
$x=\frac{8}{5}$
$x=\frac{55}{56}$