Answer:
Check attached picture.
Explanation:
Given that side length of the cube = b
We know that base of cube is a square.
So area of base = (length)(with)=(b)*(b)
or

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Volume of cube = (Lenght)(width)(hight)=(b)(b)(b)
or

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Given b=2h
divide both sides by 2
then

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From picture we can see that there are "6" square pyramids with the same base and height that exactly fill the given cube.
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So area of 1 pyramid can be found by dividing total volume of the cube by 6
so we get volume of 1 pyramid
