\[\mathbf{Страница\ 6.}\]
\[\boxed{\mathbf{10.}}\]
\[\textbf{а)}\]
\[1)\ 2\ :1\]
\[2)\ 8\ :1\]
\[3)\ 12\ :2 = 6\ :1\]
\[\textbf{б)}\ \]
\[1)\ 2\ :1\]
\[2)\ 8\ :7\]
\[3)\ 6\ :5\]
\[\boxed{\mathbf{11.}}\]
\[\frac{1}{3}\ :\frac{2}{3} = \frac{1}{3} \cdot \frac{3}{2} = \frac{1}{2} = 1\ :2.\]
\[\boxed{\mathbf{12.}}\]
\[\textbf{а)}\ в\ 3\ раза.\]
\[\textbf{б)}\ в\ 2,5\ раза.\]
\[\boxed{\mathbf{13.}}\]
\[\textbf{а)}\ \frac{a}{b} < 1\ при\ a < b.\]
\[\textbf{б)}\ \frac{a}{b} > 1\ при\ a > b.\]
\[\textbf{в)}\ \frac{a}{b} = 1\ при\ a = b.\]