\[ \frac{12}{16} = \frac{12 \div 4}{16 \div 4} = \frac{3}{4} \]
\[ \frac{18}{27} = \frac{18 \div 9}{27 \div 9} = \frac{2}{3} \]
Ответ: 1) 3/4; 2) 2/3