A circle with a radius of (a/2) is bored through the centre of a sphere of radius a. Find the volume of the remaining solid.
The Attempt at a Solution
I've been trying this for an hour now and I've been trying to find the remaining volume by finding the area of the cylinder bored + the little side bits on each side. I've just been getting really messy answers which aren't close to the actual answer.
Urgently need a hand :)