The steps of construction of similar triangles are as follows 

Draw a ray BX which makes acute angle with BC on the opposite side of vertex A.
Locate 5 points on the ray BX and mark them as B1, B2, B3, B4 and B5 such that BB1 = B1B2 = B2B3 = B3B4 = B4B5.
Join B5C
Draw a line parallel to B5C through B3 [Since 3 is the smallest among 3 and 5] and mark C’ where it intersects with BC.
Draw a line through the point C’ parallel to AC and mark A’ where it intersects AB.A’BC’ is the required triangle.
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