1.-36+69+(_17)+(-42)+32=-36+69-17-42+32=6

2.-8-(-12)-(-7)+12-20=-8+12+7+12-20=3

3.[tex]2\frac{3}{4}-(-1\frac{1}{2} )+(-3\frac{5}{6} )=\frac{11}{4}+1\frac{1}{2}-3\frac{5}{6}=\frac{11}{4}+\frac{3}{2}-\frac{23}{6}=\frac{5}{12}[/tex]