A circle of radius 4 is contained in the plane y=7.
Both circles lie on the surface of a sphere.
What is the radius of the sphere?
You're right Charlie - a careless error on my part. I should check the reasonableness of my answer. Has to be greater than 4!
Formula still works though. Same answer as you.
blackjack
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flooble's webmaster puzzle
re(2): No Subject
