Posted by luckybee on .
When you have 3 separate circles and the radius of each of those circles is 10 do i calculate like this? 2(10)+2(10)+2(10)=60 cm for my diameter

Radius Question Geometry(college level) 
Jai,
I'm not sure if there is a given figure for this problem, but if the three separate circles are tangent with the other with their centers aligned (or can be connected by a straight line), then yes, you get 60 cm for the diameter of the new, bigger circle which circumscribes on the three smaller circles.

Radius Question Geometry(college level) 
luckybee,
There are 3 separate circles, there is a chord drawn through the center of each circle, the point of tangency is on the third circle. So i drew a line perpendicular from the radius of 10 in the third circle to the point of tangency.
This is the entire question(Each of the three circles in the figure has a radius of 10. The line OA contains the centers of the three circles, and the line OB is tangent to the righthand circle. Find the length of segment CD.
Is there a way to submit my picture? 
Radius Question Geometry(college level) 
luckybee,
I solved it. the length of segment CD with by 20 cm. Thank you