Square Counting Riddles

There are 12 squares in the picture.

The trick to find it would be drawing diagonals. We know that the sides of a square are parallel and thus, the diagonals should be parallel as well. Let us begin with the outer most rectangle. See the picture. The yellow lines are diagonals drawn for reference.

http://1.bp.blogspot.com/-aGHzJWfxtEY/U2_Yh0HBt1I/AAAAAAAAC6s/VCeYXzdT1rk/s1600/how-many-squares-puzzle-solution-1.png

You can make out four squares in the image.

http://1.bp.blogspot.com/-lTktLIzp260/U2_Yh67sYFI/AAAAAAAAC68/JHsFRRPVhMs/s1600/how-many-squares-puzzle-solution-2.png

Now see the next image. You can make out a total of 8 squares - 3 blue, 3 green and 2 red. There are 4 other rectangles in the figure but they cant be square as their diagonal is not parallel with the yellow lines we drew for reference.

Thus, total squares = 4 + 8 = 12.

There are 17 squares in the given picture.
If the smallest square is of 1 unit,
Then there are 6 squares of 1 unit side, 8 squares with side 2 unit, 2 squares with ide 3 unit and 1 square with side 4 unit.

40

There are 40 squares in this picture.
Let us denote the size of squares from smaller to larger by S1, S2, S3, S4 and S5.
No. of S1 = 8
No. of S2 = 16 + 2 middle ones = 18
No. of S3 = 9
No. of S4 = 4
No. of S5 = 1

128

Lets count them one by one.
62 squares of size 1x1.
41 squares of size 2x2.
18 squares of size 3x3.
6 squares of size 4x4.
1 square of size 5x5.

62 + 41 + 18 + 6 + 1 = 128 squares.

18

16 (5+1+1+4+5)

5 black coloured squares.
1 red coloured square.
1 blue coloured square.
4 small green coloured squares in middle.
5 large green coloured squares.

The total number of squares are 17.
Let us assume that the smaller square is 1 unit in size.

Number of squares with 1 unit size = 12
Number of squares with 2 unit size = 5

There is no square with 3 unit size.

Thus total number of squares = 12 + 5 = 17.

11

66
Explanation:
Each arm has 15 blocks and there are four arms ,
The center has 6 blocks.
Total : 15*4 + 6 = 66

11