\[\boxed{Стр.\ \mathbf{24}\text{.\ \ }\mathbf{ОК\ ГДЗ\ - \ домашка\ на\ 5}}\]
\[\boxed{\mathbf{1}.}\]
\[Во\ всех\ записях\ умножение\ \]
\[заменили\ сложением\ \]
\[одинаковых\ слагаемых.\]
\[\boxed{\mathbf{2}.}\]
\[2 \cdot 5 = 10\]
\[2 + 2 + 2 + 2 + 2 = 10\]
\[4 \cdot 3 = 12\]
\[4 + 4 + 4 = 12\]
\[7 \cdot 4 = 28\]
\[7 + 7 + 7 + 7 = 28\]
\[5 \cdot 3 = 15\]
\[5 + 5 + 5 = 15\]
\[9 \cdot 2 = 18\]
\[9 + 9 = 18\]
\[\boxed{\mathbf{3}.}\]
\[8 + 8 + 8 = 8 \cdot 3 > 8 \cdot 2\]
\[4 \cdot 5 > 4 + 4 + 4 + 4 = 4 \cdot 4\]
\[6 \cdot 7 > 6 + 6 + 6 = 6 \cdot 3\]
\[1 + 1 + 1 + 1 + 1 = 1 \cdot 5\]
\[\boxed{\mathbf{4}.}\]
\[15 + 15 + 15 = 15 \cdot 3 = 45\]
\[22 + 22 + 28 = 44 + 28 = 72\]
\[52 + 25 = 77\]
\[4 + 4 + 4 + 4 = 4 \cdot 4 = 16\]
\[6 + 6 + 6 + 6 = 6 \cdot 4 = 24\]
\[3 + 3 + 3 + 3 = 3 \cdot 4 = 12\]
\[7 + 8 + 6 = 15 + 6 = 21\]
\[9 + 9 = 9 \cdot 2 = 18\]
\[7 + 7 + 7 = 7 \cdot 3 = 21\]
\[\boxed{\mathbf{5}.}\]
\[3 + 3 + 3 + 3 + 3 = 3 \cdot 5 =\]
\[= 15\ (м) - высота\ березы.\]
\[Ответ:15\ м.\]
\[\boxed{\mathbf{6}.}\]
\[1)\ 25 + 25 + 25 + 25 = 25 \cdot 4 =\]
\[= 100\ (мм) - периметр\ \]
\[первого\ квадрата.\]
\[2)\ 20 + 20 + 20 + 20 = 20 \cdot 4 =\]
\[= 80\ (мм) - периметр\ второго\ \]
\[квадрата.\]
\[3)\ 15 + 15 + 15 + 15 = 15 \cdot 4 =\]
\[= 60\ (мм) - периметр\ \]
\[третьего\ квадрата.\]
\[\boxed{\mathbf{7}.}\]
\[\boxed{\mathbf{8}.}\]
\[5 + 14 + 70 = 89\]
\[7 + 13 + 26 = 46\]
\[70 - 3 - 20 = 47\]
\[80 - 4 - 6 = 70\]
\[\boxed{\mathbf{9}.}\]
\[(35 - 30) + 8 = 5 + 8 = 13\]
\[(76 - 70) + 9 = 6 + 9 = 15\]
\[17 + 2 + 18 + 3 = 20 + 20 = 40\]
\[20 - 3 - 2 + 5 = 15 + 5 = 20\]
\[\boxed{\mathbf{Вопрос}.}\]
\[7 \cdot 3 < 7 + 7 + 7 + 7 = 7 \cdot 4\]
\[6 + 6 + 6 + 6 + 6 = 6 \cdot 5\]