progress bar with Bootstrap

I found a progress bar in Bootstrap the problem that I found when implementing it is that I can not get the bar to advance depending on a variable that I generate in the top part my question is I'm going well or there is a simpler way to do it the code is the next one

<div class="jumbotron">
                <?php
                echo'<h2>' . $obj->getDescripcion() . '</h2>';
                echo'<h2>' . $total. '</h2>';
                if ($total == $time) {
                echo'<p>se cumplio el objetivo</p>';
                } else {
                echo'<p>no se esta cumpliendo el objetivo</p>';
                }
                $progreso = ($total/$time)*100;
               echo $progreso."%";

                echo'<div class = "progress">';
                echo'<div class = "progress-bar progress-bar-striped active" role = "progressbar" aria-valuenow = "60" aria-valuemin = "0" aria-valuemax = "100" style = "width:$progreso;">'.$progreso.'';
                echo'</div>';
                echo'</div>';
                echo'</div>';
                echo'<p><a class="btn btn-primary btn-lg" href="#" role="button">Learn more</a></p>';
                echo'</div>';
                ?>
            </div>