Учебник по математике 6 класс Мерзляк

авторы: А.Г. Мерзляк, В.Б. Полонский, М.С. Якир.

издательство: Вентана-Граф, 2018 г.

Номер №290

(x + \frac{5}{12}) - \frac{9}{20} = \frac{11}{15}

x + \frac{5}{12} = \frac{11}{15} + \frac{9}{20}

x + \frac{5}{12} = \frac{44}{60} + \frac{27}{60}

x = \frac{44}{60} + \frac{27}{60} - \frac{25}{60}

x = \frac{46}{60} = \frac{23}{30}

(x - \frac{11}{30}) - \frac{16}{45} = \frac{2}{9}

x = \frac{2}{9} + \frac{11}{30} + \frac{16}{45}

x = \frac{20}{90} + \frac{33}{90} + \frac{32}{90}

x = \frac{85}{90} = \frac{17}{18}

(x - \frac{7}{15}) + \frac{5}{8} = \frac{17}{24}

x = \frac{17}{24} + \frac{7}{15} - \frac{5}{8}

x = \frac{85}{120} + \frac{56}{120} - \frac{75}{120}

x = \frac{66}{120} = \frac{11}{20}

\frac{4}{5} - (x + \frac{1}{60}) = \frac{2}{3}

x + \frac{1}{60} = \frac{4}{5} - \frac{2}{3}

x = \frac{48}{60} - \frac{40}{60} - \frac{1}{60}

x = \frac{7}{60}

4 \frac{3}{4} - (x - 2 \frac{5}{8}) = 3 \frac{5}{6}

x - 2 \frac{5}{8} = 4 \frac{3}{4} - 3 \frac{5}{6}

x = 4 \frac{18}{24} - 3 \frac{20}{24} + 2 \frac{15}{24}

x = 3 \frac{13}{24}

9 \frac{9}{28} - (4 \frac{5}{21} - x) = 6 \frac{2}{7}

4 \frac{5}{21} - x = 9 \frac{9}{28} - 6 \frac{2}{7}

4 \frac{5}{21} - x = 9 \frac{9}{28} - 6 \frac{8}{28}

4 \frac{5}{21} - x = 3 \frac{1}{28}

x = 4 \frac{20}{84} - 3 \frac{3}{84}

x = 1 \frac{17}{84}