What goes round, comes round!
Three Circles each of radius 1 touch one another externally and they lie between two parallel lines.
What is the minimum possible distance between the lines?
Source : KVPY 2011 SA Paper
Diagram not to scale
The answer is 3.73205.
This section requires Javascript.
You are seeing this because something didn't load right. We suggest you, (a) try
refreshing the page, (b) enabling javascript if it is disabled on your browser and,
finally, (c)
loading the
non-javascript version of this page
. We're sorry about the hassle.
1 solution
d min = 2 + 2 cos 3 0 = 2 + 3 = 3 . 7 3 2 units