In step 1
You have 7 dots by line and 1 line
Total 7 dots
If you sum the dots of the image for this step you find 7 dots.
In step 2
You have 8 dots by line and 2 line
Total 8 x 2=16 dots
If you sum the dots of the image for this step you find 16 dots.
In step 3
You have 9 dots by line and 3 line
Total 9 x 3= 27dots
If you sum the dots of the image for this step you find 27 dots.
In step 3
You have 10 dots by line and 4 line
Total 10 x 4=40 dots
If you sum the dots of the image for this step you find 40 dots.
Answer: 40