JSFiddle - React, Tailwind, and code Playground
HTML
<input id="qty_10" class="input-text qty" name="qty" maxlength="3" value="1" type="text" />
JavaScript
var selectedValue = 10;
$('#qty_10').attr('value', selectedValue);
<input id="qty_10" class="input-text qty" name="qty" maxlength="3" value="1" type="text" />
var selectedValue = 10;
$('#qty_10').attr('value', selectedValue);