What's the Error ? A student said that the ratios $$\dfrac{3}{4}$$ and $$\dfrac{9}{16}$$ were proportional. What error did the student make ?
$$\Rightarrow \dfrac{3}{4} = \dfrac{3 \times 4}{4 \times 4}$$
$$= \dfrac{12}{16} \neq \dfrac{9}{16}$$
Therefore, $$\dfrac{3}{4}$$ and $$\dfrac{9}{16}$$ are not proportional.