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Volume of the great pyramid

mark

The Great Pyramid of Giza has a base that is 440 cubits by 440 cubits and is 280 cubits tall. Find the volume of the Great Pyramid.

mearing

The Great Pyramid of Giza
The area of the bottom of the pyramid is

440 \mbox{ cubits} * 440\mbox{ cubits} =193600\mbox{ cubits}^2

The scaling values of the top and bottom are:

s(0)=1
s(280)=0

This means that:

s(z)=1-\frac{z}{280}

The area formula is:

A(z)=193600(1-\frac{z}{280})^2

The volume of the Pyramid is:

\int_0^{280}193600(1-\frac{z}{280})^2dz=193600\int_0^{280}1-\frac{z}{140}+\frac{z^2}{78400}dz
=193600(z-\frac{z^2}{280}+\frac{z^3}{235200})\big|_0^{280}=18069333.3 \mbox{ cubits}^3
chowell1

The Great Pyramid
The area of the base is

440 \ \text{cubits} \ \times \ 440 \ \text{cubits} \ = 193600 \ \text{cubits}^2

Since the height is 280, the scaling values of the top and bottom are:

s(0) = 1\\ s(280) = 0

This means that the scaling factor is:

s(z) = 1 \ - \ \frac{z}{280}

With this, we can determine the area formula.

A(z) = 193600(1-\frac{z}{280})^2

Now, we can find the volume of the pyramid.

\int_0^{280}193600(1-\frac{z}{280})^2dz = 193600\int_0^{280}1 - \frac{z}{140} +\frac{z^2}{78400}dz \\\
=193600(z - \frac{z^2}{280} + \frac{z^3}{235200})|^{280}_0 = 18069333.3 \ \text{cubits}^3