this is the old binary/decimal conversion
problem for fractions
<br>
either use printf/sprintf with a format-string
that does not show all decimals, for example
<br>
<?php
printf("%.2f",120 + 2.01 - 121.94);
?>
<br>
will give you only to decimals
<br>
or use the bcmath functions if you really need
the precise values