Simplifying a ratio

Question

I don't remember how to simplify a ratio from this answer:

Step 2: Calculate the required ratio \begin{align} & \text{Population of city $C$ above poverty line: population of city $G$ above poverty line} \\ =& 0.0966Y:0.0462Y \\ =& {\bf 23:11} \end{align}

I got $0.0966Y:0.0462Y$, but I'm not sure what is the equation to simplify that to $\bf 23:11$.

Answer 1

$\require{cancel}\dfrac{0.0966Y}{0.0462Y}=\dfrac{966\times\cancel{0.0001}\times\cancel{Y}}{462\times\cancel{0.0001}\times\cancel{Y}}=\dfrac{966}{462}=\dfrac{\cancel{42}\times 23}{\cancel{42}\times 11}=\dfrac{23}{11}$