\[Страница\ 42.\]
\[9.\ Приведение\ дробей\ \]
\[к\ наименьшему\ общему\ \]
\[знаменателю\]
\[\boxed{\mathbf{1.}}\]
\[\textbf{а)}\frac{5}{9} = \frac{5 \cdot 2}{18} = \frac{10}{18}\]
\[\frac{6}{7} = \frac{6 \cdot 10}{70} = \frac{60}{70}\]
\[\textbf{б)}\frac{11}{16} = \frac{44}{64}\]
\[\frac{12}{13} = \frac{36}{39}\]
\[\textbf{в)}\frac{1}{15} = \frac{6}{90}\]
\[\frac{3}{4} = \frac{240}{320}\]
\[\boxed{\mathbf{2.}}\]
\[\textbf{а)}\frac{7}{9} = \frac{140}{180}\]
\[\textbf{б)}\frac{1}{4} = \frac{45}{180}\]
\[\textbf{в)}\frac{2}{3} = \frac{120}{180}\]
\[\textbf{г)}\frac{5}{18} = \frac{50}{180}\]
\[\boxed{\mathbf{3.}}\]
\[\textbf{а)}\frac{3}{4} = \frac{6}{8}\]
\[\textbf{б)}\frac{5}{6} = \frac{15}{18}\]
\[\textbf{в)}\frac{4}{5} = \frac{24}{30}\]
\[\textbf{г)}\frac{7}{10} = \frac{56}{80}\]
\[\boxed{\mathbf{4.}}\]
\[\textbf{а)}\frac{15}{20} = \frac{3}{4} = \frac{21}{28}\]
\[\frac{21}{28} = \frac{3}{4} = \frac{27}{36}\]
\[\textbf{б)}\frac{16}{40} = \frac{2}{5} = \frac{18}{45}\]
\[\frac{28}{36} = \frac{7}{9} = \frac{63}{81}\]
\[\textbf{в)}\frac{48}{72} = \frac{2}{3} = \frac{200}{300}\]
\[\frac{35}{105} = \frac{1}{3} = \frac{2}{6}\]
\[\boxed{\mathbf{5.}}\]
\[\textbf{а)}\ наименьшему\ общему\ \]
\[кратному.\]
\[\textbf{б)}\ 1)\ НОК;\]
\[2)\ НОК,\ знаменатели,\ \]
\[дополнительный;\]
\[3)\ дополнительный.\]