In figure, if the distance between two small circles is 84,
what will be the distance between two large circles?
Source: Bangladesh Math Olympiad 2016 Junior Category
I can't solve this this problem. But I found that the connected lines between the centers of the 4 circles create a rhombus. The diagonal of the rhombus is 84.
Best Answer
Hint:
If the large circles each have radius $R$ and the small circles $r$ then: