\[\boxed{\mathbf{Проверьте\ себя.\ Страница\ 72}}\]
\[\boxed{\mathbf{Проверочная\ работа.\ Действия\ с\ рациональными\ числами\ }}\]
\[\boxed{\text{1.}}\]
\[А \Leftrightarrow 5\]
\[Б \Leftrightarrow 2\]
\[В \Leftrightarrow 1\]
\[Г \Leftrightarrow 3\]
\[Д \Leftrightarrow 4\]
\[\boxed{\text{2.}}\]
\[\textbf{а)}\ 23 \cdot ( - 6) + 27 \cdot ( - 6) =\]
\[= - 6 \cdot (23 + 27) = - 6 \cdot 50 =\]
\[= - 300\]
\[\textbf{б)} - 1\frac{1}{6} \cdot 6 - 1\frac{1}{6} \cdot 9 - 1\frac{1}{6} \cdot 3 =\]
\[= - 1\frac{1}{6} \cdot (6 + 9 + 3) =\]
\[= - \frac{7}{6} \cdot 18 = - 7 \cdot 3 = - 21\]
\[\textbf{в)} - 4\frac{1}{7} + 4,8 - 6\frac{6}{7} =\]
\[= - \left( 4\frac{1}{7} + 6\frac{6}{7} \right) + 4,8 =\]
\[= - 10\frac{7}{7} + 4,8 = - 11 + 4,8 =\]
\[= - 6,2\]
\[\boxed{\text{3.}}\]
\[\textbf{а)} - 3,75 \cdot 0 < 24 \cdot 1\]
\[\textbf{б)} - 3\frac{7}{8} \cdot 12 = - 12 \cdot 3\frac{7}{8}\]
\[\boxed{\text{4.}}\]
\[( - 18,4 + 3,16) + 12,47 =\]
\[= - 18,4 + (3,16 + 12,47) =\]
\[= - 18,4 + 15,63 =\]
\[= - (18,40 - 15,63) = - 2,77\]
\[\boxed{\text{5.}}\]
\[\textbf{а)}\ \frac{23}{- 24} = - \frac{23}{24}\]
\[\textbf{б)}\ \frac{- 12}{- 25} = \frac{12}{25}\]
\[\textbf{в)} - \frac{33}{- 35} = \frac{33}{35}\]
\[\textbf{г)} - \frac{- 45}{- 49} = - \frac{45}{49}\]
\[\boxed{\text{6.}}\]
\[\left( - \frac{5}{12} + \frac{11}{16} \right)\ :\left( - \frac{13}{72} \right) =\]
\[= \left( \frac{33}{48} - \frac{20}{48} \right) \cdot \left( - \frac{72}{13} \right) =\]
\[= \frac{13}{48} \cdot \left( - \frac{72}{13} \right) = - \frac{9}{6} = - \frac{3}{2} =\]
\[= - 1,5\]