Today's mentalfloss.com Brain Game is a new Free-for-all Friday challenge. Good luck!

Which one letter of the English alphabet is missing from the following list, and why?

a, b, d, e, g, o, q

Here is the SOLUTION.

ANSWER:

The missing letter is p.

Those are the only lower-case letters in the alphabet that contain a closed shape. None of the others - c, f, h, i, j, k, l, m, n, r, s, t, u, v, w, x, y, z - have one.

Please join us on Monday for a new Monday Math Square!