Question

If a new sidewalk will be 5 feet wide, 100 feet long and filled to a depth of 9 inches (0.75 foot) with concrete how many cubic yards of concrete are needed

Answer 1

(5 ft)*(100 ft)*(0.75 ft) * ((1 yd)/(3 ft))³ ≈ 13 8/9 yd³

About 13.89 cubic yards of concrete are needed.