[tex]9=3\cdot3\\15=3\cdot5\\\\\frac{9}{15}=\frac{\not3^1\cdot3}{\not3_1\cdot5}=\boxed{\frac{3}{5}}\\\\other\ answers\\\\\frac{3\cdot2}{5\cdot2}=\boxed{\frac{6}{10}}\\\\\frac{3\cdot4}{5\cdot4}=\boxed{\frac{12}{20}}\\\\\frac{3\cdot5}{5\cdot5}=\boxed{\frac{15}{25}}\\\vdots[/tex]