Answer: They need 20 more meters of tape.
This is because they are putting tape around the perimeter. To find the perimeter you add up each side.
This is shown like this
20+20+40+40=120meters.
But the question is asking how many more meters of tape does the company so we subtract the amount of tape they already which is 100meters from 120meters.
So it can be written like this
120m -100m = 20meters of tape
Answer: the company needs 20 more meters of tape.