Which of the following are not proportional
a).
[tex] \frac{ 6}{8} \: and \frac{9}{12} [/tex]
b).
[tex] \frac{24}{6} \: and \: \frac{8}{2} [/tex]
c).
[tex] \frac{9}{12} \: and \: \frac{10}{15} [/tex]
d).
[tex] \frac{7}{3} \: and \: \frac{21}{49} [/tex]
e).
[tex] \frac{21}{49} \: and \frac{4}{7} [/tex]
f).
[tex] \frac{3}{8} \: and \: \frac{9}{32} [/tex]
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