The idea is to measure relative sizes. So if your first sphere has radius r and the second sphere has radius R, where R = 3r, you can then reason about which n

The idea is to measure relative sizes. So if your first sphere has radius r and the second sphere has radius R, where R = 3r, you can then reason about which n maximizes volume for each. Remember that volume is going to be in units of r (and R) to the power of n.