1. 计算：$5\frac{3}{5}+(-1\frac{7}{8})+2\frac{2}{5}+(-3\frac{5}{12})+2\frac{7}{8}+(-12\frac{7}{12}).$

$-7$

2. 计算：
(1) $(-12.5)×(+317)×(-\dfrac{4}{5})×(-0.1)$；
(2) $-1^2 - (\dfrac{2}{3} - \dfrac{7}{8} + \dfrac{1}{12} - \dfrac{5}{6})×(-24)$；
(3) $48\dfrac{24}{25}÷(-48)$；
(4) $7777×138\dfrac{7}{9} + \dfrac{2}{9}÷(-\dfrac{1}{7777}) - 38\dfrac{5}{9}×7777$；
(5) $(-\dfrac{4}{5})×\dfrac{5}{13} - (-\dfrac{3}{5})÷(-2\dfrac{3}{5}) - \dfrac{5}{13}×(-1\dfrac{3}{5})$。

(1) $-317$
(2) $-24$
(3) $-1\dfrac{1}{50}$
(4) $777\ 700$
(5) $\dfrac{1}{13}$

3. 计算：$(-\dfrac{1}{36})÷(\dfrac{1}{3}-\dfrac{5}{6}+\dfrac{5}{12}-\dfrac{2}{9}-2\dfrac{1}{4}).$

$\dfrac{1}{92}$