一、填空题
1. $(+3)+(-8)=$
2. $(-3)+(-15)=$
3. $0-2=$
4. $(-3)-2=$
5. $(-3)-(-5)=$
6. $(-4\dfrac{2}{3})+(+3\dfrac{1}{6})=$
7. $(-8\dfrac{2}{3})+(+4.5)=$
8. $(-5)-(+6)-(-5)=$
9. $(-10)-($ $)=-2$
10. $(-23)+($ $)=-1.25$

1. -5 2. -18 3. -2 4. -5 5. 2 6. $-1\dfrac{1}{2}$ 7. $-4\dfrac{1}{6}$ 8. -6 9. -8 10. 21.75

二、计算题
11. $(-8)-(+4)+(-5)-(-2)$
12. $-20+(-14)-(-18)-13$
13. $(+1.25)+(-\frac{1}{2})+(-\frac{3}{4})-1\frac{3}{4}$
14. $(-0.5)-(-3\frac{1}{4})+2.75-(+7\frac{1}{2})$
15. $(+12)-(-18)+(-7)-(+15)$
16. $\frac{2}{5}-\left|-1\frac{1}{2}\right|-(+2\frac{1}{4})-(-2.75)$
17. $-0.75+3\frac{4}{9}+\left|-\frac{3}{4}\right|+(-5\frac{1}{2})+\left|-2\frac{5}{9}\right|$
18. $-12\frac{1}{3}-[10\frac{1}{4}-3\frac{2}{3}+(-8\frac{3}{4})]$

11. -15 12. -29 13. $-1\dfrac{3}{4}$ 14. -2 15. 8 16. -0.6 17. $\dfrac{1}{2}$ 18. $-10\dfrac{1}{6}$