If △PQR ~ △ABC, PQ = 6 cm, AB = 8 cm and perimeter of △ABC is 36 cm, then perimeter of △PQR is

1. 20.25 cm

2. 27 cm

3. 48 cm

4. 64 cm

Let perimeter of △PQR be x cm.

Since triangles are similar,

$\therefore \dfrac{\text{PQ}}{\text{AB}} = \dfrac{\text{Perimeter of △PQR}}{\text{Perimeter of △ABC}} \\[1em] \Rightarrow \dfrac{6}{8} = \dfrac{x}{36} \\[1em] \Rightarrow x = \dfrac{6 \times 36}{8} \\[1em] \Rightarrow x = 27.$

∴ Perimeter of △PQR = 27 cm.

Hence, Option 2 is the correct option.