Answer:
5 cubes
Step-by-step explanation:
The volume of a square pyramid is given in terms of its side length (s) and height (h) as ...
V = (1/3)s^2·h
For the given measurements, the volume is ...
V = (1/3)(9 cm)^2 ·(10 cm) = 270 cm^3
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The volume of each cube of wax is the product of its length, width, and height, so is ...
V = (4 cm)^3 = 64 cm^3
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Then the number of wax cubes required to fill the pyramid is ...
(270 cm^3)/(64 cm^3/cube) = 4 7/32 cubes
Four cubes are not quite enough to make the candle.
Devin will need 5 cubes to make the candle.