Question

We want to cover the bed with a layer of mulch 3 inches thick. How many cubic feet of mulch will we need?

Answer 1

To find how many cubic feet we need to find the volume of the flower bed. The volume is given by:

$V=Bh$

where B is the area of the base and h is the height.

In this case the height would be 3 inches (0.25 ft) and the area of the base is:

$B=\frac{1}{2}\cdot6\cdot6=18$

Therefore the volume is:

$V=18\cdot0.25=4.5$

Hence we need 4.5 cubic feet of mulch