Final answer:
The perimeter P of the rectangular garden can be represented as the function P(w) = 10w, where w is the width of the garden.
Step-by-step explanation:
The perimeter P of a rectangular garden can be represented as a function of the width w by adding up all the sides of the garden. In this case, the length of the garden is four times the width, so we can write the equation as:
P(w) = 2w + 2(4w) = 2w + 8w = 10w
Therefore, the correct representation of the perimeter P of the garden as a function of the width w is P(w) = 10w.