Rounding Mechanism to nearest 0.05

Question

I would like to solve rounding mechanism by using php4,5.2 and below (not 5.3) Currently I am doing 0.05 rounding, something like this page:

http://www.bnm.gov.my/in

Answer 1

Expanding a little on @xtofl to allow for more precise steps (not technically required for this question)

    $step         = 0.0005;
    $multiplicand = floor($value / $step);
    $rest         = fmod($value, $step);

    $value = $step * $multiplicand;

    if ($rest > $step / 2) {
        $value += $step;
    }