Castle windows

Seven twelfth windows in the castle are in the shape of an n-gon. Six-fourteenths of these windows are quadrilateral in shape, while two-ninths of them are square windows. How many windows are there in the castle if there are 15 square windows?

Final Answer:

x =  270

Step-by-step explanation:

$$\begin{gathered} \frac{7}{12}\cdot \frac{6}{14}\cdot \frac{2}{9}\cdot x=15 \\ 7/12\cdot 6/14\cdot 2/9\cdot x=15 \\ 14x=3780 \\ x=\frac{3780}{14}=270 \\ x=270 \end{gathered}$$

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