ГДЗ Математика 6 клас Істер — Вправа 1100

1) $\frac{4}{17} + (-\frac{3}{17}) + (-\frac{5}{17}) + \frac{6}{17} = (\frac{4}{17} + \frac{6}{17}) + (-\frac{3}{17} - \frac{5}{17}) = \frac{10}{17} - \frac{8}{17} = \frac{2}{17};$

2) $\frac{3}{20} + (-\frac{7}{20}) + \frac{9}{20} + (-\frac{11}{20}) = (\frac{3}{20} + \frac{9}{20}) + (-\frac{7}{20} - \frac{11}{20}) = \frac{12}{20} - \frac{18}{20} = -\frac{6}{20} =$

$= -0,3;$

3) $-\frac{4}{7} + \frac{13}{19} + (-\frac{3}{7}) + 2\frac{6}{19} = (-\frac{4}{7} - \frac{3}{7}) + (\frac{13}{19} + 2\frac{6}{19}) = -1 + 3 = 2;$

4) $-2\frac{1}{3} + 5\frac{2}{3} + 7\frac{1}{3} + (-9\frac{1}{3}) = (-2\frac{1}{3} - 9\frac{1}{3}) + (5\frac{2}{3} + 7\frac{1}{3}) = -11\frac{2}{3} + 13 = 1\frac{1}{3};$

5) $4\frac{1}{7} + 2\frac{5}{9} + (-4\frac{7}{9}) + (-4\frac{1}{7}) = (4\frac{1}{7} - 4\frac{1}{7}) + (2\frac{5}{9} - 4\frac{7}{9}) = 0 - 2\frac{2}{9} = -2\frac{2}{9};$

6) $-\frac{1}{2} + (-1\frac{1}{2}) + (-2\frac{1}{2}) + 5 + (-3\frac{1}{2}) = (-\frac{1}{2} - 1\frac{1}{2} - 2\frac{1}{2} - 3\frac{1}{2}) + 5 =$

$= -8 + 5 = -3.$