160827

A really easy way to figure out how many soldiers are in the hollow square (or how many dots there are) is to times the outside by itself, for example: if there is 16 dots on the single, top line you would times 16 by 16 (16x16). Then times the inside of the square by itself, for example: if there is 10 dots on the single, top line on the inside, you would multiply 10 by itself (10x10).
16x16=256
10x10=100
Once you know what they equal, you take the 'inside number' from the 'outside number' (256-100), which is 156. So now you know that the hollow square has 156 soldiers (or dots).