Question 1106948
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There are infinitely many solutions.


For any integer  n  (positive,  negative or zero)  the number  x = n + 0.2  is the solution.


There are NO other solutions.


For example,  the numbers   0.2,  1.2,   5.2,   -0.8,  -12.8  are the solutions.



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Regarding the function floor(x), see this Wikipedia article

<pre>
    https://en.wikipedia.org/wiki/Floor_and_ceiling_functions
</pre>

Its definition is <U>THIS</U>:


<pre>
    In mathematics, the floor function is the function that takes as input a real number x and gives as output the greatest integer 
    that is less than or equal to  x.
</pre>