Devin needs 5 cubes of wax to make the candle.
First, we need to get the volume of the candle.
Remember that for a square pyramid, the volume is equal to the product between the base and the height divided by 3.
In this case, the base is:
B = 9cm*9cm = 81cm²
And the height is H = 10cm, then the volume is:
V = 81cm²*10cm/3 = 270cm³
While each cube of wax has a volume of:
v = (4cm)³ = 64cm³
To see the number of cubes that we need, we need to take the quotient between the two volumes:
N = V/v = 270/64 = 4.22
Rounding to the next whole number, we get N = 5.
Devin needs 5 cubes of wax to make the candle.
If you want to learn more about volumes:
https://brainly.com/question/1972490
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