Puzzles - Missing letters puzzles

Exercise : Missing letters puzzles
181.
Answer
:
S
Explanation
:
Starting at the top left of the diagram, and moving in a Z shape, letters advance through the alphabet in steps of 5.

182.
Answer
:
Y
Explanation
:
Start with the top point of each star, and move clockwise around the other points. Letters advance through the alphabet in steps of 5 for the left hand star, 6 for the central star, and 7 for the right hand star.

183.
Answer
:
Q
Explanation
:
Working in columns, add the numerical value of the top and middle letters together to give the numerical value of the lower letter.