Construct a triangle of sides 4 cm, 5 cm, and 6 cm and then a triangle similar to it whose sides are 2/3 of the corresponding sides of the first triangle.

Steps of construction:

1. Draw a base BC of length 6 cm.
2. Place the pointed end of the compass on B and mark an arc of radius 5 cm. Now, place the pointed end on C and mark an arc of radius 4 cm intersecting with the previous arc. Mark this intersection point as A.
3. Join A−B and A−C. △ABC is the first triangle.
4. Draw a ray BX from point B on the opposite side of A to line BC.
5. Mark three equidistant points on ray BX and name them B1, B2 and B3.
6. Join B3−C. From B2, draw a line parallel to B3C and let it intersect BC in D. From D draw a line parallel to AC and let it intersect AB in E. △BED is the required similar triangle.