\[\boxed{\mathbf{Стр.\ 12.\ }еуроки - ответы\ на\ пятёрку}\]
\[\boxed{\mathbf{22.}}\]
\[1)\ x\ :1 = 18\]
\[x = 18.\]
\[1 \cdot x = 27\]
\[x = 27.\]
\[36\ :x = 36\]
\[x = 1.\]
\[2)\ 72 = x \cdot 8\]
\[x = 72\ :8\]
\[x = 9.\]
\[63\ :x = 9\]
\[x = 63\ :9\]
\[x = 7.\]
\[x\ :8 = 6\]
\[x = 6 \cdot 8\]
\[x = 48.\]
\[\boxed{\mathbf{23.}}\]
\[63 - 59 = 4\ (ребенка) - ушло\ \]
\[из\ хора.\]
\[Ответ:4\ ребенка.\]
\[\boxed{\mathbf{24.}}\]
\[47 + 27\ :9 = 47 + 3 = 50\]
\[60\ :3\ :4 = 20\ :4 = 5\]
\[50 - 42\ :6 = 50 - 7 = 43\]
\[9 \cdot (90 - 83) = 9 \cdot 7 = 63\]
\[80\ :(38 - 18) = 80\ :20 = 4\]
\[90\ :30 \cdot 8 = 3 \cdot 8 = 24\]
\[\boxed{\mathbf{25.}}\]
\[6\ дм = 60\ см < 63\ см\]
\[8\ мм < 1\ см = 10\ мм\]
\[1 \cdot 15 = 15\ :1\]
\[10 + 0 = 10 - 0\]
\[18\ :9 < 18\ :6\]
\[21\ :3 > 12\ :3\]