Question : $\triangle ABC \sim \triangle DEF$ and the perimeters of $\triangle ABC$ and $\triangle DEF$ are 40 cm and 12 cm respectively. If DE = 6 cm then AB is:

Question : If $\triangle ABC \sim \triangle QRP, \frac{\operatorname{area}(\triangle A B C)}{\operatorname{area}(\triangle Q R P)}=\frac{9}{4}, A B=18 \mathrm{~cm}, \mathrm{BC}=15 \mathrm{~cm}$, then the length of $\mathrm{PR}$ is:

Question : $\Delta ABC$ and $\Delta DEF$ are two similar triangles and the perimeters of $\Delta ABC$ and $\Delta DEF$ are 90 cm and 54 cm respectively. If the length of DE = 36 cm, then the length of AB is: 

Question : $\triangle ABC \sim \triangle DEF$ such that AB = 9.1 cm and DE = 6.5 cm. If the perimeter of $\triangle DEF = 25$ cm, then the perimeter of $\triangle ABC$ is:

Question : For congruent triangles $\triangle$ABC and $\triangle$DEF, which of the following statements is correct?