Answer:
4.63 cubic yard.
Step-by-step explanation:
Given,
The length of sidewalk, l = 100 feet,
Width, w = 5 feet,
Depth, h = 3 inches = 0.25 feet,
Thus, the volume of the concrete needed for making the sidewalk,
![V=l\times w\times h](https://tex.z-dn.net/?f=V%3Dl%5Ctimes%20w%5Ctimes%20h)
![=100\times 5\times 0.25](https://tex.z-dn.net/?f=%3D100%5Ctimes%205%5Ctimes%200.25)
= 125 cubic feet,
∵ 1 cubic yard = 27 cubic feet,
⇒ 1 cubic feet =
cubic yard,
Thus, the quantity of concrete needed =
≈ 4.63 cubic yard.