\[\boxed{\mathbf{41.}}\]
\[2 \cdot 7 = 14\]
\[14\ :2 = 7\]
\[14\ :7 = 2\]
\[3 \cdot 9 = 27\]
\[27\ :3 = 9\]
\[27\ :9 = 3\]
\[4 \cdot 6 = 24\]
\[24\ :4 = 6\]
\[24\ :6 = 4\]
\[5 \cdot 9 = 45\]
\[45\ :5 = 9\]
\[45\ :9 = 5\]
\[6 \cdot 5 = 30\]
\[30\ :5 = 6\]
\[30\ :6 = 5\]
\[7 \cdot 4 = 28\]
\[28\ :4 = 7\]
\[28\ :7 = 4\]
\[8 \cdot 3 = 24\]
\[24\ :3 = 8\]
\[24\ :8 = 3\]
\[9 \cdot 6 = 54\]
\[54\ :6 = 9\]
\[54\ :9 = 6\]
\[8 \cdot 4 = 32\]
\[32\ :4 = 8\]
\[32\ :8 = 4\]
\[7 \cdot 3 = 21\]
\[21\ :3 = 7\]
\[21\ :7 = 3\]
\[9 \cdot 2 = 18\]
\[18\ :2 = 9\]
\[18\ :9 = 2\]
\[5 \cdot 7 = 35\]
\[35\ :7 = 9\]
\[35\ :5 = 7\]