Is there a question that contains no numbers except $1$, whose answer is $\pi/7$?

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Is there a question that contains no numbers, except possibly $1$, whose answer is $\pi/7$ ?

There are plenty of questions with no numbers except $1$, whose answer is $\pi/n$ for small integer values of $n$ other than $7$. For some reason, $\pi/7$ seems to be unattainable.

Examples:

  1. Evaluate $\int_{-\infty}^\infty \frac{\sin{x}}{x}dx$. Answer: $\color{red}{\pi}$

  2. Drop a needle of length $1$ onto a floor with equally spaced parallel lines a distance $1$ apart. On average, how many times do you have to drop the needle until it crosses one of the lines? Answer: $\color{red}{\pi/2}$

  3. What is the volume of a cone with unit base radius and unit height? Answer: $\color{red}{\pi/3}$

  4. A regular $n$-gon of side length $1$ encloses a regular $(n+1)$-gon. The polygons are concentric, and for each $n$ the area of the inside polygon is maximized. What is the limit, as $n\to\infty$, of the difference in their areas? Answer: $\color{red}{\pi/4}$

  5. On a sphere of diameter $1$, uniformly random points are chosen until there is a unique circle that passes through them. What is expected area of this (planar) circle? Answer: $\color{red}{\pi/5}$

  6. A regular $n$-gon of side length $1$ is inscribed in a circle. What is the limit, as $n\to\infty$, of the difference between their areas? Answer: $\color{red}{\pi/6}$

  7. $\color{red}{???}$

  8. Like question 4, except the polygons do not have to be concentric. Answer: $\color{red}{\pi/8}$

Indirectly specifying a number is not allowed; for example, "heptagon" is equivalent to "$7$-gon" and is thus not allowed. The question should not be obviously ad hoc. (For example: "A unit circle is divided into $k$ equal parts, where $k$ is the product of the first even prime and the first odd prime, plus $1$. What is the area of each part?") I hope the spirit of my question is understood.

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You hinted at an answer in a comment:

A circle of radius $1$ is partitioned into sectors by radial lines, all of these sectors having equal area. What is the area of the largest such sector that cannot be constructed by compass and straightedge?

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Question :
The Unit Circle is Dissected into $C$ Smaller Circles of Equal Size.
The $C$ Smaller Circles are arranged on the Euclidean Plane such that every Circle is Either touching every other Circle Or can reach every other Circle with a Single Circle in-between.
In other words , Every Circle is neighbours with every other Circle or it has a Common neighbour with the non-neighbouring Circles.
Every Pair of Circles will be made of neighbours or will have a Common neighbour.

What is the Minimum Area of those $C$ Smaller Circles ?


Dissection may not be the appropriate word. I will restate with other words :
The Unit Circle is covered with White Paint. Paints in various other colours will be given to colour a Set of Smaller Circles such that the total Paint Quantity is Equal to the White Paint Quantity , which is naturally $\pi$ Units.
The Smaller Circles are required to be arranged such that every Pair $(C_n,C_m)$ have a Common neighbouring Circle or are neighbours themselves.

What is the Minimum Paint Quantity of each colour ?


Answer :
$\pi/7$


Elaboration :
Basically Unit Circle Area = $\pi$ , Each Smaller Circle has Area $\pi/C$.

With $C=2,3,4,5$ , we have :
C=2,3,4,5

With $C=6$ , this will not work :
6 WRONG
The 2 Purple Circles are not neighbours & have no Common neighbours.

With $C=6$ , this will work :
C=6

With $C=7$ , this will not work :
7 WRONG
Here , the Purple Circle is too far from the Grey Circles.

Maximum $C$ is 7. We can arrange these Circles like this :
1+6=7

Every Circle is neighbours with every other Circle Or Every Circle is neighbours with the Centre Circle which is the Common Neighbour with the non-neighbouring Circles.
We can not have larger $C$.
Hence , Minimum Area of those $C$ Smaller Circles is $\pi/C=\pi/7$.
This is the Minimum Paint Quantity of each colour.


With $C=8$ , there is no way.
8 WRONG
Here , the Grey Circle is too far from the Purple Circles.