Answer: (1) 13/20 (2) 8 (3) Yes. They are proportional
Step-by-step explanation:
(1) 13 students take the bus.
33 - 13 = 20 students do not take the bus
[tex]\dfrac{\text{take the bus}}{\text{do not take the bus}}:\dfrac{13}{20}[/tex]
(2)
[tex]\dfrac{2\ red}{3\ green}=\dfrac{x}{12\ green}\\\\\\\underline{\text{cross multiply}:}\\2(12)=3(x)\\24=3x\\8=x[/tex]
(3)
[tex]\dfrac{6}{10}\div \dfrac{2}{2}\quad =\dfrac{3}{5}\\\\\\\dfrac{9}{15}\div \dfrac{3}{3}\quad =\dfrac{3}{5}\\\\\\\dfrac{15}{25}\div \dfrac{5}{5}\quad =\dfrac{3}{5}[/tex]
All of the fractions simplify to the same number so they ARE proportional.