How to know how many people are in a march

... there were 50,000 people
I've never seen so many people
... we are 300,000

Well, well, let's give some basic lessons to this, using common sense tools, so we have fun while passing the political crisis. This is an example, where the central square was full, I tried to find a better image but it was not possible so I show this:

1. How to know the area

The simplest way, is to use Google Earth, with the pinche measurement tool that for these purposes tantiometric has validity. The entire plaza measures 103 × 60 meters, which gives us an approximate area of ​​6,180 square meters.

This is the total area of ​​the square, including inaccessible areas such as green areas that people respect or monuments. But let's assume that this compensates for the surrounding areas.

2. How to know how many people

The ideal is an aerial image where you can see the covered areas, but for this case, even assuming that the whole square was full, which is not true, would be to divide the area of ​​the square between the area occupied by a person in a concentration.

We will handle in this case 0.36 square meters per person, questionable according to the euphoria, the tone of the intestinal gases or the size of banners that require space, but is an example for this exercise.

So the total number of people would be:

6,180 m2 / 0.36 m2 = 17,166 people. (If the whole square was full)

The media reported that there were 50,000, almost 3 times what fits in the whole square

On the other hand, the march that started from the Pedagogical University, considering that it reached Natural Resources, which was completely full, including the gutters, gutters without lids, or craters that the mayor has not covered. I use that as a reference to compare, because right now it is happening and it could be that the length is greater (or less) depending on the ideological point of view, that only the helicopter that now flies over my house will be able to prove it.

Length: 1,000 meters, Width: 9.75 meters (because it is only one way), so we would have an area of ​​9,750 square meters.

9,750 / 0.36 = 27,083 people.

There were those who reported that 300,000 had people, almost eleven times more than can fit in that area

3. How to know who lies

The fault is again with the politicians, who usually give figures of their concentrations that serve as a foolish reference and that are not equivalent when we remember what it means to have a full stadium. So politicians confuse us (for the umpteenth time), and people play along to that benchmark. 

Another way to calculate them would be to count the feet and divide it between two, hehe; but if you do not want to complicate using Google Earth, is to divide the total that the media say between the average of the sum of years of your children and perhaps that is a fact closer to reality.

Let's see if this crisis ends and let us work quietly.