This one is going to be brief, but I find it interesting. A buddy of mine a few months back sent me a text about this realization: The geometric mean is just the arithmetic mean of the exponents! I'll explain in a second but just a quick background.
An arithmetic mean is what we commonly refer to as the average: add all the elements up and divide by the number of elements.
$$\overline{x}=\frac{x_1+x_2+\cdots+x_n}{n}$$
Alternatively, the we have the geometric mean. Except the geometric mean is the multiplicative analog to the arithmetic mean. The geometric mean is the $n$th root of the product of the elements.
$$\overline{y}'=\left(y_1y_2\cdots y_n\right)^{\frac{1}{n}}$$
The connection is as follows. Each number $y_i$ (assuming they are all positive) can be expressed as $y_i=a^{b_i}$ for some $a,b\in\mathbb{R}$. Therefore we have the following
$$\begin{align*}
\overline{y}'&=\left(y_1y_2\cdots y_n\right)^{\frac{1}{n}}\\
&=\left(a^{b_1}a^{b_2}a^{b_2}\cdots a^{b_n}\right)^{\frac{1}{n}}\\
&=\left(a^{b_1+b_2+\cdots+b_n}\right)^{\frac{1}{n}}\\
&=a^{(b_1+b_2+\cdots+b_n)/n}
\end{align*}$$
which states that if each $y_i$ can be expressed as $y_i=a^{b_i}$ for some $a\in\mathbb{R}$ and $b_i\in\mathbb{R}$ then the geometric mean of all $y_i$ is the base, $a$, raised to the arithmetic mean of all exponents $b_i$.
$$\overline{y}'=a^{\overline{b}}$$ Pretty interesting, eh?
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