\[\boxed{\mathbf{Страница}\mathbf{\ \ 22}\mathbf{.}\mathbf{\ }Еуроки\ - \ ДЗ\ без\ мороки}\]
\[\boxed{\mathbf{41}\mathbf{.}\mathbf{\ }}\]
\[24\ :8 = 3\]
\[6 \cdot 3 = 18\]
\[27\ :3 = 9\]
\[24 - 8 = 16\]
\[24 + 8 = 32\]
\[9\ :3 = 3\]
\[27 - 9 = 18\]
\[12 + 3 = 15\]
\[12\ :3 = 4\]
\[18\ :3 = 6\]
\[3 \cdot 4 = 12\]
\[27 + 9 = 36\]
\[\boxed{\mathbf{42}\mathbf{.}}\ \]
\[В\ одной\ стопке\ могло\ быть\ \]
\[тетрадей:\]
\[1\ и\ 9;\]
\[2\ и\ 8;\]
\[3\ и\ 7;\]
\[4\ и\ 6;\]
\[5\ и\ 5.\]
\[Саша\ разложил\ тетради\ в\ две\ \]
\[РАВНЫЕ\ стопки.\]
\[10\ :2 = 5\ (тетрадей) - в\ одной\ \]
\[стопке.\]
\[Ответ:5\ тетрадей.\]
\[\boxed{\mathbf{43}\mathbf{.}\mathbf{\ }}\]
\[24\ :8 \cdot 4 = 3 \cdot 4 = 12\]
\[21\ :3 \cdot 2 = 7 \cdot 2 = 14\]
\[15\ :5 \cdot 3 = 3 \cdot 3 = 9\]
\[27\ :9 \cdot 4 = 3 \cdot 4 = 12\]
\[21\ :7 \cdot 6 = 3 \cdot 6 = 18\]
\[16\ :8 \cdot 6 = 2 \cdot 6 = 12\]
\[6 \cdot 2\ :4 = 12\ :4 = 3\]
\[32\ :4 \cdot 6 = 8 \cdot 6 = 48\]
\[\boxed{\mathbf{44}\mathbf{.}\mathbf{\ }}\]
\[x \cdot 7 = 14\]
\[x = 2.\]
\[x\ :3 = 9\]
\[x = 27.\]
\[20\ :x = 5\]
\[x = 4.\]