In which of the following situations, does the list of numbers involved in the form of a GP.?
Perimeter of each triangle, when the mid points of sides of equilateral triangle whose side is 24 cm are joined to form another triangle, whose mid points in turn are joined to form still another triangle and the process continues indefinitely.
It has been already given that the perimeter of any figure is drawn by using the midpoint of the same figure in GP.
If the perimeter of that triangle is “a” then the perimeter of the triangles formed by using midpoint is 
, 
….,
Perimeter of a triangle is = s1 + s2 + s3 = 24 + 24 + 24 = 72
In the same way the perimeter of given triangle is 72
The perimeter of the triangles formed by using midpoint will be 36, 18, 9
We can see that their common ratios is same
R1 = 
R2 = 