A construction crew has just built a new road. They built 43.75 kilometers of road at a rate of 7 kilometers per week. How many weeks did it take them?

Let w = weeks
7 kilometers per week * w = 43.75

To solve for w, we divide each side of the equation by 7:
7w/7 = 43.75/7

Cancel the 7's, we get:
w = 6.25