Yes, you can do it with html5 elements and jQuery, like this:
HTML:
JS:
var slider = $('#chance_slider'),
textbox = $('#chance');
slider.change(function() {
var newValue = parseInt($(this).val());
textbox.val(newValue);
});
textbox.change(function() {
var newValue = parseInt($(this).val());
slider.val(newValue);
});
EDIT
To allow decimals:
var slider = $('#chance_slider'),
textbox = $('#chance');
slider.change(function() {
var newValue = $(this).val();
textbox.val(newValue);
});
textbox.change(function() {
var newValue = $(this).val();
slider.val(newValue);
});