Division solution for PHP

About PHP division $ abc = 285083800; $ truit = 10000000; $ abc = $ abc/$ truit; the result is: 28.508379999999998943849277566 instead of: 28.5083800 is a software interface PHP, I don't know what the software has done to get the value accurate to so many decimal places below. how can I tell you about PHP division?
$ Abc = 285083800;
$ Truit = 10000000;

$ Abc = $ abc/$ truit;

The resulting value is: 28.508379999999998943849277566.
Instead of: 28.5083800

It is a software interface PHP, and I don't know what the software has done to get the value accurate to so many decimal places below
How can I write code to set the value to 28.5083800?


Which of the following is the complete code? thank you!

------ Solution --------------------
$ Abc = 285083800;
$ Truit = 10000000;

$ Abc = $ abc/$ truit;


Echo number_format ($ abc, 7 ,'.','');

// 28.5083800