\[\boxed{\mathbf{1}\mathbf{.6}}\]
\[\textbf{а)}\ 42\ :7 \cdot 8 = 6 \cdot 8 = 48\]
\[60 \cdot 5\ :10 = 300\ :10 = 30\]
\[630\ :9 \cdot 3 = 70 \cdot 3 = 210\]
\[\textbf{б)}\ 72\ :8 \cdot 3 = 9 \cdot 3 = 27\]
\[44\ :4 \cdot 2 = 11 \cdot 2 = 22\]
\[360\ :4\ :3 = 90\ :3 = 30\]
\[\textbf{в)}\ 12 \cdot 3\ :9 = 36\ :9 = 4\]
\[46\ :2 \cdot 3 = 23 \cdot 3 = 69\]
\[280\ :4\ :7 = 70\ :7 = 10\]
\[\textbf{г)}\ (37 + 11)\ :24 = 48\ :24 = 2\]
\[(53 - 39) \cdot 6 = 14 \cdot 6 = 84\]
\[49\ :(71 - 64) = 49\ :7 = 7\ \]