\[\boxed{\mathbf{38\ (38)}\mathbf{.}\mathbf{\ }Еуроки\ - \ ДЗ\ без\ мороки}\]
\[1)\ 83\ :7 = 11\ (ост.\ 6)\ \ \ \ \ \]
\[83 = 7 \cdot 11 + 6\]
\[2)\ 171\ :17 = 10\ (ост.\ 1)\]
\[171 = 17 \cdot 10 + 1\]
\[\boxed{\mathbf{38}.}\]
\[1)\ 6(b + 9) = 6b + 54\]
\[2)\ (c - 2d) \cdot 14 = 14c - 28d\]
\[3)\ 10(4a + 5b - 9c) =\]
\[= 40a + 50b - 90c\]