Puzzles - Missing letters puzzles

Answer

:

Y

Explanation

:

Starting with the bottom left letter and moving in a clockwise spiral towards the centre, letters advance through the alphabet in steps of 4, 5, 6 etc.

Answer

:

E

Explanation

:

Starting with the bottom row and moving up, one row at a time, the sum of the numerical values of the letters starts at 26 for the bottom row, then 24, 22 and 20 as you move up.

Answer

:

X

Explanation

:

Starting with the bottom right hand corner, and moving in a clockwise spiral towards the centre, letters advance through the alphabet, skipping 4 letters at a time.