Count the number of 3\(\times\)6 rectangles in the 50\(\times\)39 grid above.
I'm lazy to draw new grids by the way.
Details and assumptions:
- Dimensions are expressed as width\(\times\)height. Thus a 3\(\times\)6 rectangle (that is, a rectangle of width 3 and height 6) is considered to be different to a 6\(\times\)3 (width 6 height 3) rectangle, in this case, you only want the 3\(\times\)6 rectangles, not the 6\(\times\)3 ones.