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\[План\] | \[Действительность\] |
---|---|
\[4\ см\] | \[400\ см = 4м\] |
\[2\ см\] | \[200\ см = 2\ м\] |
\[1\ см\] | \[100\ см = 1\ м\] |
\[S = 4 \cdot 2 + 2 \cdot 1 = 8 + 2 =\]
\[= 10\ \left( м^{2} \right) - площадь\ комнаты.\]
\[Ответ:10\ м^{2}.\]
\[\boxed{\mathbf{9.}}\]
\[2\frac{1}{8} + 3\frac{2}{3} + 4\frac{7}{8} + 1\frac{1}{3} =\]
\[= \left( 2\frac{1}{8} + 4\frac{7}{8} \right) + \left( 3\frac{2}{3} + 1\frac{1}{3} \right) =\]
\[= 7 + 5 = 12\]
\[3\frac{1}{2} + \left( 2\frac{3}{4} + 1\frac{1}{2} \right) =\]
\[= \left( 3\frac{1}{2} + 1\frac{1}{2} \right) + 2\frac{3}{4} =\]
\[= 4\frac{2}{2} + 2\frac{3}{4} = 7\frac{3}{4}\]
\[2\frac{7}{8} + \left( 1\frac{3}{5} + 1\frac{1}{8} \right) =\]
\[= \left( 2\frac{7}{8} + 1\frac{1}{8} \right) + 1\frac{3}{5} = 4 + 1\frac{3}{5} =\]
\[= 5\frac{3}{5}\]
\[7\frac{1}{2} - \left( 1\frac{3}{8} + 1\frac{1}{2} \right) =\]
\[= \left( 7\frac{1}{2} - 1\frac{1}{2} \right) - 1\frac{3}{8} = 6 - 1\frac{3}{8} =\]
\[= 5\frac{8}{8} - 1\frac{3}{8} = 4\frac{5}{8}\]
\[9\frac{1}{16} - \left( \frac{5}{8} + \frac{7}{16} \right) =\]
\[= \left( 8\frac{17}{16} - \frac{7}{16} \right) - \frac{5}{8} =\]
\[= 8\frac{10}{16} - \frac{10}{16} = 8\]
\[7\frac{3}{4} + \left( 2\frac{7}{8} - 1\frac{3}{4} \right) =\]
\[= \left( 7\frac{3}{4} - 1\frac{3}{4} \right) + 2\frac{7}{8} = 6 + 2\frac{7}{8} =\]
\[= 8\frac{7}{8}\]
\[3\frac{7}{8} + \left( 2\frac{3}{5} - 1\frac{5}{8} \right) =\]
\[= \left( 3\frac{7}{8} - 1\frac{5}{8} \right) + 2\frac{3}{5} =\]
\[= 2\frac{2}{8} + 2\frac{3}{5} = 2\frac{1}{4} + 2\frac{3}{5} =\]
\[= 2\frac{5}{20} + 2\frac{12}{20} = 4\frac{17}{20}\]
\[3\frac{7}{8} - \left( 2\frac{3}{8} - 1\frac{3}{4} \right) =\]
\[= \left( 3\frac{7}{8} - 2\frac{3}{8} \right) + 1\frac{3}{4} =\]
\[= 1\frac{4}{8} + 1\frac{3}{4} = 1\frac{2}{4} + 1\frac{3}{4} = 2\frac{5}{4} =\]
\[= 3\frac{1}{4}\]
\[5\frac{1}{6} \cdot 4 + 2\frac{5}{6} \cdot 4 + 8\frac{1}{2} \cdot 4 =\]
\[= 4 \cdot \left( 5\frac{1}{6} + 2\frac{5}{6} \right) + 4 \cdot 8\frac{1}{2} =\]
\[= 4 \cdot 8 + 4 \cdot \frac{17}{2} = 32 + 34 = 66\]
\[3\frac{1}{2} \cdot 2 + 2\frac{1}{2} \cdot 2 + 3\frac{1}{2} \cdot 2 =\]
\[= 2 \cdot \left( 3\frac{1}{2} + 2\frac{1}{2} + 3\frac{1}{2} \right) =\]
\[= 2 \cdot 8\frac{3}{2} = 2 \cdot \frac{19}{2} = 19\]