\[\boxed{\mathbf{Стр.\ 64.\ }еуроки - ответы\ на\ пятёрку}\]
\[\boxed{\mathbf{1.}}\]
\[300 \cdot 3 = 900\]
\[500\ :5 = 100\]
\[120 \cdot 6 = 720\]
\[240\ :4 = 60\]
\[160\ :8 = 20\]
\[480\ :30 = 48\ :3 = 16\]
\[150 \cdot 2 = 300\]
\[160 \cdot 4 = 640\]
\[\boxed{\mathbf{2.}}\]
\[1)\ 7 \cdot 3 - 1 \cdot 1 = 21 - 1 =\]
\[= 20\ \left( м^{2} \right) - надо\ вскопать.\]
\[2)\ 20\ :4 = 5\ (дней) - хозяин\ \]
\[будет\ работать.\]
\[Ответ:5\ дней.\]
\[\boxed{\mathbf{3.}}\]
\[50\ :8 = 6\ (ост.\ 2)\]
\[6 \cdot 8 + 2 = 48 + 2 = 50\]
\[60\ :9 = 6\ (ост.\ 6)\]
\[6 \cdot 9 + 6 = 54 + 6 = 60\]
\[65\ :9 = 7\ (ост.\ 2)\]
\[7 \cdot 9 + 2 = 63 + 2 = 65\]
\[18\ :7 = 2\ (ост.\ 4)\]
\[2 \cdot 7 + 4 = 14 + 4 = 18\]