If 6m by 15m is a pond, is 40m would be enough for fencing the pond

If the pond were a rectangle, then:

length=15 m

width=6 m

We would have to calculate the perimeter of this rectangle.

Perimeter of a rectangle=2 (length) + 2 (width)

Perimeter of this rectangle=2 (15 m) + 2 (6 m) = 30 m+12 m=42 m

We need 42 m and I only have 40 m, therefore, it would not be enough for fencing the pond.