\[\boxed{\text{Страница}\text{\ 19.}\text{\ }\text{Еуроки\ -\ ДЗ\ без\ мороки}}\]
\[52.\]
\(10.\)
\[53.\]
\[230 \cdot 14 + 270 \cdot 14 =\]
\[= 500 \cdot 14 = 7000\]
\[23 \cdot 140 + 27 \cdot 140 = 50 \cdot 140 =\]
\[= 500 \cdot 14 = 7000\]
\[230 \cdot 140 + 270 \cdot 140 =\]
\[= 500 \cdot 140 = 70\ 000\]
\[78 \cdot 120 - 28 \cdot 120 =\]
\[= 50 \cdot 120 = 6000\]
\[780 \cdot 12 - 280 \cdot 12 = 500 \cdot 12 =\]
\[= 50 \cdot 120 = 6000\]
\[780 \cdot 120 - 280 \cdot 120 =\]
\[= 500 \cdot 120 = 60\ 000\]
\[54.\]
\(1)\)
\[2)\ 388\ 190\ :1 = 388\ 190\]
\[3)\ 0\ :(508 \cdot 207 - 48\ 319) = 0\]
\(4)\ \)
\[5)\ 470\ 954 - 0 = 470\ 954\]
\[55.\]
\(10\ 969;\)
\(15\ 800.\)