ГДЗ Математика 6 клас Істер — Вправа 299

1) $3\frac{1}{8} + 9\frac{1}{12} - 6\frac{5}{6} = 3\frac{3}{24} + 9\frac{2}{24} - 6\frac{20}{24} =$

$= 12\frac{5}{24} - 6\frac{20}{24} = 11\frac{29}{24} - 6\frac{20}{24} = 5\frac{9}{24} = 5\frac{3}{8};$

2) $5\frac{3}{5} + 4\frac{11}{15} - 8\frac{1}{12} = 5\frac{36}{60} + 4\frac{44}{60} - 8\frac{5}{60} =$

$= 9\frac{80}{60} - 8\frac{5}{60} = 10\frac{20}{60} - 8\frac{5}{60} = 2\frac{15}{60} = 2\frac{1}{4};$

3) $3\frac{9}{10} - 1\frac{5}{12} - 1\frac{11}{24} = 3\frac{108}{120} - 1\frac{50}{120} - 1\frac{55}{120} =$

$= 2\frac{58}{120} - 1\frac{55}{120} = 1\frac{3}{120} = 1\frac{1}{40};$

4) $13\frac{5}{6} - 8\frac{1}{4} - 5\frac{1}{3} = 13\frac{10}{12} - 8\frac{3}{12} - 5\frac{4}{12} =$

$= 5\frac{7}{12} - 5\frac{4}{12} = \frac{3}{12} = \frac{1}{4};$

5) $7\frac{3}{8} - (4\frac{5}{6} + 1\frac{3}{4}) = 7\frac{9}{24} - (4\frac{20}{24} + 1\frac{18}{24}) =$

$= 7\frac{9}{24} - 5\frac{38}{24} = 7\frac{9}{24} - 6\frac{14}{24} = 6\frac{33}{24} - 6\frac{14}{24} = \frac{19}{24};$

6) $12 - (5\frac{5}{6} + 3\frac{3}{10}) = 12 - (5\frac{25}{30} + 3\frac{9}{30}) =$

$=12 - 8\frac{34}{30} = 12 - 9\frac{4}{30} = 11\frac{30}{30} - 9\frac{4}{30} = 2\frac{26}{30} = 2\frac{13}{15}.$