Puzzles - Missing letters puzzles

Answer

:

Y

Explanation

:

Starting in the top left circle, and following a W pattern through the others, letters in corresponding segments of the circles follow the alphabetical sequence in steps of 4 letters.

Answer

:

W

Explanation

:

Working from left to right, letters move forwards 7 places, then back 2. Repeat this sequence until the end.

Answer

:

K

Explanation

:

In each row, the product of the left and right hand numbers equals the sum of the numerical values of the three letters.