JSFiddle - React, Tailwind, and code Playground

HTML

<table id="mytable">
<tr><td>Adam</td><td id="x">$50</td></tr>
<tr><td>Evan</td><td>$20</td></tr>
<tr><td>Frank</td><td>$80</td></tr>
<tr><td>Harold</td><td>$90</td></tr>
<tr><td>Zarold</td><td>$20</td></tr>
<tr><td>Jeff</td><td>$20</td></tr>
<tr><td>Linus</td><td>$10</td></tr>
<tr><td>Sam</td><td>$87</td></tr>
<tr><td>Zach</td><td>$100</td></tr>
</table>

CSS

td {
    padding: 4px;
    border-bottom: 1px solid blue;
}
td:last-child {
    text-align: right;
}
td.colorize {
    color: red;
}

JavaScript

var arr = $('#mytable').find('td:last-child').map( function(){
    var cleanval = parseInt( $(this).text().replace('$',''),10);
    $(this).addClass('s_'+cleanval);
    return cleanval;
}).get().sort( function(a,b){ return (b-a); } ).slice(4);

for( var i=0,j=arr.length;i<j;i++ ) {
    $('td.s_'+arr[i]).addClass('colorize');
}