The formula to find the perimeter of a rectangle is P = 2(l + w), where p is perimeter, l is length and w is width,
The length of the playground is 16 yards, and the width is 20, because 16 x 20 = 320 and 16 + 4 = 20.
P = 2(l + w)
P = 2(16 + 20)
P = 2(36)
P = 72.
The perimeter is 72 yards.
Hope this helps!!