What is the volume of the pyramid in the diagram?

Answer: 1500 cubic centimeters
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Work Shown:
area of square base = length*width = 20*15 = 300 square cm
multiply this by the height to get 300*15 = 4500, then divide by 3 to end up with 4500/3 = 1500
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Here's how it would look with a formula
V = (L*W*H)/3
V = (20*15*15)/3
V = (300*15)/3
V = 4500/3
V = 1500
Note how we don't need to use the value 25 in the diagram.