Pi is sometimes called Archimedes’s constant because he devised an early scheme for approximating the constant’s value. Anaxagoras, another Greek philosopher, considered the problem of squaring the circle (that is, finding a square with the same area as a given circle). There are in fact several references in Ulysses to Leopold Bloom working on this mathematical problem as well; alas, he was unsuccessful because, as a consequence of the 1882 Lindemann–Weierstrass theorem which proves that pi is a transcendental number, squaring the circle is impossible.
The thirteen answers to this meta can be arranged in rows to form a griddy circle:
Although there are several ways to assemble the answers to form a circle because of answers with the same length, there is only one way such that CIRCLE X CIRCLE (squaring the circle, get it?) reads down the central column.
Note that there are exactly 121 letters among all the answers. As suggested by the flavortext (and the idea of creating a square with the same area as a given circle), we can lay out this same set of answers to form an 11×11 square by entering them in row-major order:
Now read down the second and tenth column to obtain the meta solution CONSIDERS DUBLIN THE CUBE. (Doubling the cube is another impossible-to-achieve problem in geometry, also known to the ancient Greeks.)