\[\boxed{\mathbf{1.}}\]
\[\textbf{а)}\ 18\ 050\ 007\]
\[\textbf{б)}\ 209\ 000\ 025\]
\[\textbf{в)}\ 6\ 034\ 000\ 708\]
\[\boxed{\mathbf{2.}}\]
\[18\ 307 > 1948\]
\[777\ 777 > 555\ 555\]
\[360\ 289\ 524 < 360\ 298\ 520\]
\[4\ < 7*\]
\[**3 > \ **9\]
\[1**\ > 8*\]
\[\boxed{\mathbf{3.}}\]
\[408\ 075 =\]
\[= 400\ 000 + 8000 + 70 + 5\]
\[\boxed{\mathbf{4.}}\]
\[50\ 000 + 300 + 10 + 9 = 50\ 319\]
\[7\ 000\ 000 + 80\ 000 + 400 + 60 =\]
\[= 7\ 080\ 460\]
\[\boxed{\mathbf{5.}}\]
\[\textbf{а)}\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ Проверка:\]
\[\textbf{б)}\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ Проверка:\]
\[\boxed{\mathbf{6.}}\]
\[\textbf{а)}\ x\ :40 = 23\]
\[x = 23 \cdot 40\]
\[x = 920.\]
\[\textbf{б)}\ 14 \cdot x = 70\]
\[x = 70\ :14\]
\[x = 5.\]
\[\textbf{в)}\ 96\ :x = 8\]
\[x = 96\ :8\]
\[x = 12.\]
\[\boxed{\mathbf{7.}}\]
\[1)\ 9 + 6 = 15\ (дм) - длина\ \]
\[прямоугольника.\]
\[2)\ 2 \cdot (9 + 15) = 48\ (дм) -\]
\[периметр\ прямоугольника\ \]
\[(и\ квадрата).\]
\[3)\ 48\ :4 = 12\ (дм) - сторона\ \]
\[квадрата.\]
\[4)\ 12 \cdot 12 = 144\ \left( дм^{2} \right) -\]
\[площадь\ \ квадрата.\]
\[Ответ:144\ дм^{2}.\]
\[\boxed{\mathbf{8.}}\]
\[Между\ 4\ столбами\ \]
\[3\ промежутка.\]
\[48\ :3 = 16\ (м) - расстояние\ \]
\[между\ каждыми\ двумя\ \]
\[соседними\ столбами.\]
\[Ответ:16\ м.\]
\[\boxed{\mathbf{9.}}\]
\[\textbf{а)}\ 80 \cdot (4 - 3) \cdot 6 = 480\]
\[\textbf{б)}\ 7 \cdot (30 + 18\ :3) = 252\]
\[\textbf{в)}\ (80\ :20 + 4) \cdot 5 = 40\]
\[\textbf{г)}\ (54\ :3 \cdot 2 + 4)\ :4 = 10\]