Problem:
A straight concrete sidewalk is to be feet wide, feet long and inches thick. How many cubic yards of concrete must a contractor order for the sidewalk if concrete must be ordered in a whole number of cubic yards?
Answer Choices:
A.
B.
C.
D.
E. more than
Solution:
The number of cubic feet is . Since there are cubic feet in cubic yard, there are cubic yards of concrete required. Thus cubic yards must be ordered.
Since feet yard, feet yards. Also inches yard. Thus cubic yards of concrete are needed, so cubic yards must be ordered.
Answer: .
The problems on this page are the property of the MAA's American Mathematics Competitions