JSFiddle - React, Tailwind, and code Playground
HTML
<span id=target>$150</span>
JavaScript
$target = $('span#target');
text = $target.text();
$target.text('R'+text.substring(1));
<span id=target>$150</span>
$target = $('span#target');
text = $target.text();
$target.text('R'+text.substring(1));