JSFiddle - React, Tailwind, and code Playground
HTML
<input type="checkbox" value="3.99" id="one" >
<input type="checkbox" value="5.99" id="two">
<input type="checkbox" value="7.99" id="three">
JavaScript
var $cbs = $(':checkbox');
$cbs.change(function(){
var total = 0; //$("#more").val();
$cbs.each(function() {
if ($(this).is(":checked"))
total += parseFloat($(this).val());
});
alert(total);
});