Предмет: Алгебра, автор: olenaalistratova7

пж помогитееееееннннннннн

Приложения:

Ответы

Автор ответа: Vopoxov

Объяснение:

$14 \tfrac{7}{15} - 3 \tfrac{3}{23} \cdot \tfrac{23}{27} - 1 \tfrac{1}{5} \cdot \tfrac{1}{6} = \\ = \tfrac{15 \cdot14 + 7}{15} - \tfrac{3\cdot23 + 3}{23} \cdot \tfrac{23}{27} - \tfrac{5 + 1}{5} \cdot \tfrac{1}{6} = \\ = \tfrac{210 + 7}{15} - \tfrac{69 + 3}{23} \cdot \tfrac{23}{27} - \tfrac{5 + 1}{5} \cdot \tfrac{1}{6} = \\ \large = \tfrac{217}{15} - \tfrac{72}{23} \cdot \tfrac{23}{27} - \tfrac{6}{5} \cdot \tfrac{1}{6} = \\ \large = \tfrac{217}{15} - \tfrac{ \cancel{9 \ }\cdot8}{\cancel{23}} \cdot \tfrac{\cancel{23}}{ \cancel{9 \ }\cdot3} - \tfrac{ \cancel{6 \ }}{5} \cdot \tfrac{1}{ \cancel{6 \ }} = \\ \large = \tfrac{217}{15} - \tfrac{ 8}{ 3} - \tfrac{1}{5} = \tfrac{217}{5 \cdot3} - \tfrac{ 8 \cdot5}{ 3 \cdot5} - \tfrac{1 \cdot3}{5 \cdot3} = \\ \large \tfrac{217 - 40 - 3}{15} = \tfrac{174}{15} = \tfrac{58 \cdot\cancel{3}}{5 \cdot\cancel{3}} = \tfrac{58}{5} = \\ = 11 \tfrac{3}{5} = 11.6$

$(5 \tfrac{8}{9} :1\tfrac{17}{36} + 1\tfrac{1}{4}) \cdot\tfrac{5}{21} = \\ = (\tfrac{45 + 8}{9} :\tfrac{36 + 17}{36} + \tfrac{4 + 1}{4}) \cdot\tfrac{5}{21} = \\ = (\tfrac{53}{9} \cdot\tfrac{36}{53} + \tfrac{5}{4}) \cdot\tfrac{5}{21} = \\ = (\tfrac{\cancel{53}}{\cancel{9 \: }} \cdot\tfrac{\cancel{9 \ } \cdot4}{\cancel{53}} + \tfrac{5}{4}) \cdot\tfrac{5}{21} = (4 + \tfrac{5}{4}) \cdot\tfrac{5}{21} = \\ = (\tfrac{16}{4} + \tfrac{5}{4}) \cdot\tfrac{5}{21} = \tfrac{16 + 5}{4} \cdot\tfrac{5}{21} = \tfrac{\cancel{21}}{4} \cdot\tfrac{5}{\cancel{21}} = \\ = \frac{5}{4} = 1 \frac{1}{4} = 1.25$

$( - 1\tfrac{3}{8}- 2\tfrac{5}{12}): 5\tfrac{5}{12} = \\ = ( - \tfrac{8 + 3}{8}- \tfrac{24 + 5}{12}): \tfrac{60 + 5}{12} = \\ = ( - \tfrac{11}{8}- \tfrac{29}{12}) \cdot \tfrac{12}{65} = \\ = ( - \tfrac{11}{2 \cdot4}- \tfrac{29}{ 3\cdot4}) \cdot \tfrac{12}{65} = \\ = ( - \tfrac{11 \cdot3}{2 \cdot3\cdot4}- \tfrac{29 \cdot2}{ 2\cdot3\cdot4}) \cdot \tfrac{12}{65} = \\ = - \tfrac{33 + 58}{24} \cdot \tfrac{12}{65} = \\ = - \tfrac{33 + 58}{2 \cdot \cancel{12}} \cdot \tfrac{ \cancel{12}}{65} = - \tfrac{91}{130} = - \tfrac{ \cancel{13} \cdot7}{ \cancel{13} \cdot10} = \\ = - \frac{7}{10} = - 0.7$