Floating point values have a limited precision. Hence a value might 
not have the same string representation after any processing. That also
includes writing a floating point value in your script and directly 
printing it without any mathematical operations.

If you would like to know more about "floats" and what IEEE
754 is, read this:
http://www.floating-point-gui.de/

Thank you for your interest in PHP.

hi , thanks for the quick reply , 
but if you try another number like .


<?php
$dNumber = 1.2;
$dExponential = 100;
$x = ($dExponential*$dNumber);
var_dump($x);
var_dump(ceil($x));

Expected result:
----------------
120

Actual result:
--------------
120



only the float of 110 is returning a wrong unexpected number .

My reply had a link which explains what is happening.