Puzzles - Missing letters puzzles

Answer

:

N

Explanation

:

Start on the left, and move to the right. Letters advance through the alphabet in steps of 2, then 3, then 4 etc.

Answer

:

T

Explanation

:

In each triangle, start with the bottom left letter, and move clockwise around the other points. Letters advance through the alphabet in steps given by the numerical value of the letter at the centre of the triangle.

Answer

:

4

Explanation

:

Splitting the diagram in half horizontally and vertically, each quarter contains the alphabet written in sequence, with the relative position of this sequence rotating 1/4 turn anti-clockwise as you move clockwise around the quarters.