\[\boxed{\mathbf{Страница}\mathbf{\ 72}\mathbf{.}\mathbf{\ }Еуроки\ - \ ДЗ\ без\ мороки}\]
\[\boxed{\mathbf{47}\mathbf{.}\mathbf{\ }}\]
\[\boxed{\mathbf{48}\mathbf{.}\mathbf{\ }}\]
\[3\ см\ 5\ мм + 4\ см\ 5\ мм = 8\ см\]
\[P = 4a = 8\ см \Longrightarrow a = 2\ см.\]
\[\boxed{\mathbf{49}\mathbf{.}\mathbf{\ }}\]
\[211\ м\ 20\ см \cdot 4 = 844\ м\ 80\ см\]
\[8\ ц\ 37\ кг \cdot 2 = 16\ ц\ 74\ кг\]
\[\boxed{\mathbf{50}\mathbf{.}\mathbf{\ }}\]
\[D - L = 500 - 50 = 450\]
\[XV + C = 15 + 100 = 115\]
\[LXX - V = 70 - 5 = 65\]
\[CXV - XXV = 115 - 25 = 90\]