
161. 

Answer: X
Explanation:
In each triangular shape, start on the extreme left and move in a clockwise spiral towards the centre. Letters are written in alphabetical order, in steps of 6 letters for the left hand shape, 7 letters for the centre, and 8 letters for the right hand shape.

162. 

Answer: B
Explanation:
Start on the left of the diagram, and work in columns, top to bottom,from left to right. Letters are written in sequence, in steps of 2,then 4, then 6, then 8, before repeating this pattern.

163. 

Answer: Y
Explanation:
Work in rows, across the 4 squares as a whole. Start at the top left and move to the right, then down one row and to the left etc in a snakes and ladders pattern. Letters advance through the alphabet in steps of 5 letters at a time.

164. 

Answer: W
Explanation:
In each row, take the reverse alphabetical value of the left hand letter and the alphabetical value of the right hand letter and calculate the difference, putting this result in the central square.

165. 

Answer: F
Explanation:
Taking pairs of letters at opposite sides of the diagram, the sum of their numerical values equals 21 each time.


