The perimeter of a square is 1/5 meter. find the length of each side in meters?

The perimeter of a square is the sum of all sides. Since a square has 4 sides, you have to divide 1/5 meters (0.2m) by 4

1/5 : 1/4 = 1/20 (you're basically multiplying the denominators, as the numerator has to be divided by 5 and then 4)

Or 0.2 : 5 = 0.04