SQL float columns: select "where x = 2.0" works, but "where x = 2.1" does not - mysql

Question

I have a Ruby on Rails app with a model Project, which has an attribute wcag_version of type float.
I have a record with wcag_version = 2 and one with wcag_version = 2.1:
What I noticed is that Rails finds the record with wcag_version = 2 using Project.where(wcag_version: 2.0):
[4] pry(#<WcagElementsController>)> Project.where(wcag_version: 2.0)
=> [
[0] #<Project:0x007f9fa900c6e8> { :id => 1 ... }
But it doesn't find the record with wcag_version = 2.1 using Project.where(wcag_version: 2.1):
[5] pry(#<WcagElementsController>)> Project.where(wcag_version: 2.1)
=> []
It seems to be an SQL issue, not a Rails issue though. The generated SQL is:
[6] pry(#<WcagElementsController>)> Project.where(wcag_version: 2.1).to_sql
=> "SELECT `projects`.* FROM `projects` WHERE `projects`.`wcag_version` = 2.1 ORDER BY `projects`.`name` ASC"
Which doesn't return anything either if I execute it manually directly on the database:
What's going on here? I'm using MySQL by the way.

Answer 1

Dealing with Rails, it seems that I can work around the problem like this:
Project.all.each do |project|
if project.wcag_version >= reference_criterion.wcag_version
# Do stuff
end
end
While this is less performant, it saves me a lot of headache.
For sake of completeness, here's the original code:
Project.where("wcag_version >= #{reference_criterion.wcag_version}").each do |project|
# Do stuff
end