The problem is that you are using a sketch pattern instead of a feature pattern in your equation. Delete the pattern in both sketches, leaving only a single slot on each side. Use a feature pattern on each Cut-Extrude.
Double-click the feature pattern and pick the number that is for the pattern quantity, then use the same equation you used in the sketch pattern.
This gives you the correct # of slots on each side, but the first and last slot are not always centered on the part. Do you manually change the distance from the first slot to the edge so the part will be symmetrical, or are all your lengths divisible by 100?
For example, if your width is 560mm, the first slot is 50mm to the edge and the last one is 10mm.