Question

# If triangles ABC and DEF are similar and AB = 4 cm, DE = 6 cm, EF = 9 cm and FD = 12 cm, the perimeter of triangle is,

- 22 cm
- 20 cm
- 21 cm
- 18 cm

Hint:

### If all the three sides of a triangle are in proportion to the three sides of another triangle, then the two triangles are similar. Thus, if AB/XY = BC/YZ = AC/XZ then ΔABC ~ΔXYZ.

## The correct answer is: 18 cm

We know that , perimeter of a triangle is the sum of all sides of a triangle.

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