Puzzles - Missing letters puzzles

Answer

:

W

Explanation

:

Starting with the top left outer segment and moving clockwise, letters advance through the alphabet in steps of 4, then 5, 6, 7 etc. The letters in the inner segments follow the same pattern, but move anti-clockwise.

Answer

:

G

Explanation

:

Starting at the top left and working anti-clockwise towards the centre in a spiral, letters advance through the alphabet in steps of 8 at a time.

Answer

:

F

Explanation

:

Taking pairs of letters in adjacent segments, their numerical values always add up to 10.