1) -42 + 54 + (-13) + (-26) + 32 = -42 + 54 - 13 - 26 + 32 = 5
2) 8 + (-13) - (-11) - (-7) - 42 = 8 - 13 + 11 + 7 - 42 = -29
3) $$4\frac{5}{9}+(-3\frac{7}{15})-(\frac{-2}{5})=4\frac{5}{9}-3\frac{7}{15}+\frac{2}{5}=4\frac{25}{45}-3\frac{21}{45}+\frac{18}{45}=1\frac{22}{45}$$
Ответ: 1) 5; 2) -29; 3) $$1\frac{22}{45}$$