<s>[INST] Solving proportions with $3$ ratios,$ x:3:y = -2:3:-4$ Proportion seems simple enough for me. Example is $4:x = 2:5,$ and the answer is $x = 10.$
My problem is how do I solve for proportions with $3$ ratios like $x:3:y = -2:3:-4$ ?
Do I write it like
$$\frac{\frac{x}{3}}{y} = \frac{\frac{-2}{3}}{-4} $$
?
 [/INST] We have: $x:3:y=-2:3:-4$
$\Rightarrow x:3=-2:3$
$\Rightarrow \dfrac{x}{3}=-\dfrac{2}{3}$
$\Rightarrow x=-2$
and
$\Rightarrow 3:y=3:-4$
$\Rightarrow \dfrac{3}{y}=-\dfrac{3}{4}$
$\Rightarrow \dfrac{y}{3}=-\dfrac{4}{3}$
$\Rightarrow y=-4$
$\therefore x=-2,y=-4$
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