Answer:
7 squares
Explanation:
Key skills: Counting, Averages
1) Based on what I counted, there are 11 columns, and 53 squares. If you want an average of 5 squares per column and you have 12 columns, the total number of squares you want is 60.
2) Since there are already 53 squares present, you need 60-53 = 7 squares more.
Hope you understood and have a nice day!!