The triangles $\triangle BCD$ and $\triangle FGH$ are similar by the SSS Similarity Theorem, as their corresponding sides are proportional:

$\frac{13.5}{30} = \frac{18}{40} = \frac{27}{60}$

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Expanding Questions:

1. How do we verify proportionality in SSS similarity?
2. What is the role of angle comparison in similarity?
3. How can the similarity ratio be used to find unknown sides?
4. What are other similarity criteria besides SSS?
5. How can the similarity of triangles be applied in practical problems?

Tip: Always verify all three side ratios when using the SSS similarity theorem to confirm triangle similarity.