Question

Помогите!!! Даю 20 баллов

Answer 1

1) (-3,9+3,9)+(4,7-4,7)+8,6=8,6
2)
$4 frac{3}{8} + 5 frac{1}{8} - 3 frac{3}{7} - 9 frac{1}{2} = \ = 9 frac{4}{8} - 3 frac{3}{7} - 9 frac{1}{2} = \ = 9 frac{1}{2} - 9 frac{1}{2} - 3 frac{3}{7} = - 3 frac{3}{7}$
3)
$(4 frac{9}{14} - 3 frac{3}{14} + 1 frac{1}{14} ) - \ - ( frac{5}{12} + 3 frac{1}{12} ) = \ (1 frac{6}{14} + 1 frac{1}{14} ) - 3 frac{6}{12} = \ = 2 frac{7}{14} - 3 frac{1}{2} = 2 frac{1}{2} - 3 frac{1}{2} = - 1$
4)
$3 frac{1}{3} - frac{8}{10} - 2 frac{3}{4} + 2 frac{5}{10} + \ + frac{3}{10} + 1 frac{7}{12} = \ = (3 frac{1}{3} - 2 frac{3}{4} + 1 frac{7}{12} ) - \ - ( frac{8}{10} - frac{25}{10} - frac{3}{10} )= \ = (frac{10}{3} - frac{11}{4} + frac{19}{12} ) - frac{20}{10} = \ = frac{40 - 33 + 19}{12} - 2 = frac{26}{12} - 2 = \ = 2 frac{2}{12} - 2 = frac{1}{6}$