What are the dimensions of the base of each footing?

Question

The problem

 

 

Sam is filling holes with cement to make footings for his deck. Each hole is 1 1/4 feet deep and has a square base. Sam needed 22.5 cubic feet of cement to fill eight holes. What are the dimensions of the base of each footing?

 

 

In the problem there will be formula and algerbra so can anyone help me please?

Answer 1

Shivangi,

 

There's definitely a formula but not much algebra. You have 22.5 cubic feet of cement to fill eight holes that are all cubes, and each hole is the same shape so they each use 2.8125 cubic feet. The volume of each hole is base*height where the base is the side of the square, squared. I guess your best formula is side^2*height=volume.

 

Here height is 1.25 and volume is 2.8125, making side^2=2.25 and the side 1.5 feet.

 

Hope that helps!