Puzzles - Number puzzles

163.
Answer
:
4
Explanation
:
Working in rows, add the left and right hand values together and subtract 3 to give the number in the centre of each row.

164.
Answer
:
4
Explanation
:
Add together the four outer numbers of each grid. This answer is the central number of the grid one place further clockwise.

165.
Answer
:
10
Explanation
:
Working in columns, the sum of the numbers in each column equals 23.