△ ABC is such that AB = 3 cm, BC = 2 cm and CA = 2.5 cm.△ DEF is similar to △ABC. If EF = 4 cm, then the perimeter of △DEF is
15 cm
Given that ΔABC∼ΔDEF
and AB = 3 cm, BC = 2 cm and CA = 2.5 cm, EF = 4 cm.
∴ABDE=ACDF=BCEF∵ΔABC∼ΔDEF
⟹BCEF=24=12
⟹ Corresponding sides of ΔDEF are twice the sides of ΔABC
DE = 6 cm, EF = 4 cm, DF = 5cm.
∴ Perimeter of △DEF
= (DE + EF + DF) = 15 cm.