Решебник по алгебре и начала математического анализа 11 класс Алимов Задание 1244

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\[1)\ 10\ :\frac{1}{8} = x\ :1\frac{1}{4}\]

\[10 \bullet \frac{8}{1} = x\ :\frac{4 + 1}{4}\]

\[80 = x \bullet \frac{4}{5}\]

\[x = 80 \bullet \frac{5}{4} = 20 \bullet 5 = 100.\]

\[Ответ:\ \ x = 100.\]

\[2)\ x\ :0,75 = 9\frac{1}{2}\ :14\frac{1}{4}\]

\[x\ :\frac{75}{100} = \frac{9 \bullet 2 + 1}{2}\ :\frac{14 \bullet 4 + 1}{4}\]

\[x \bullet \frac{100}{75} = \frac{19}{2} \bullet \frac{4}{57}\]

\[\frac{100}{75}x = \frac{2}{3}\]

\[x = \frac{2}{3} \bullet \frac{75}{100} = \frac{25}{50} = \frac{1}{2}.\]

\[Ответ:\ \ x = \frac{1}{2}.\]

\[3)\ \frac{x}{15} = \frac{1,456}{1,05}\]

\[\frac{x}{15} = \frac{1456}{1050}\]

\[x = \frac{1456}{1050} \bullet \frac{15}{1} = \frac{1456}{70} = 20,8.\]

\[Ответ:\ \ 20,8.\]