\[\boxed{\text{31.}}\]
\[45\ :9 = 5\]
\[18\ :2 = 9\]
\[36\ :9 = 4\]
\[54\ :9 = 6\]
\[72\ :9 = 8\]
\[36\ :9 = 4\]
\[81\ :9 = 9\]
\[27\ :9 = 3\]
\[\boxed{\text{32.}}\]
\[49\ :7 = 7 \longrightarrow 63\ :9 = 7\]
\[48\ :8 = 6 \longrightarrow 2 \cdot 3 = 6\]
\[72\ :9 = 8 \longrightarrow 2 \cdot 4 = 8\]
\[36\ :4 = 9 \longrightarrow 72\ :8 = 9\]
\[\boxed{\text{33.}}\]
\[2 \cdot 4 = 8\]
\[72\ :9 = 8\]
\[45\ :9 = 5\]
\[16\ :2 = 8\]
\[4 \cdot 1 = 4\]
\[3 \cdot 3 = 9\]
\[3 \cdot 8 = 24\]
\[7 \cdot 9 = 63\]
\[9 \cdot 2 = 18\]
\[4 \cdot 9 = 36\]
\[9 \cdot 9 = 81\]
\[9 \cdot 3 = 27\]
\[10 \cdot 3 = 30\]
\[70\ :7 = 10\]
\[10 \cdot 8 = 80\]
\[60\ :3 = 20\]
\[20 \cdot 4 = 80\]
\[90\ :3 = 30\]
\[1)\ однозначные\ числа;\]
\[2)\ двузначные\ числа;\]
\[3)\ круглые\ числа.\ \]
\[\boxed{\text{34.}}\]
\[1)\ 18\ :3 = 6\ (ватрушек) - \ \]
\[испекла\ бабушка.\]
\[2)\ 6 + 9 = 15\ (пирожков) - с\ \]
\[вареньем\ испекла\ бабушка.\]
\[3)\ 18 + 6 + 15 = 24 + 15 = 39\ \]
\[(пирожков\ и\ ватрушек) -\]
\[испекла\ всего.\]
\[Ответ:\]
\[39\ пирожков\ и\ ватрушек.\]