JSFiddle - React, Tailwind, and code Playground

by Gereltod Gotsbayar

HTML

<select class="num1">
    <option>5</option>
    <option>10</option>
    <option>15</option>
    <option>20</option>
</select>
<select class="num2">
    <option>5</option>
    <option>10</option>
    <option>15</option>
    <option>20</option>
</select>
<div>буруу: <span class="wrong"></span></div>
<div>зөв: <span class="correct"></span></div>

JavaScript

$("select").change(function(){

    $wrong = $(".num1 option:selected").text() + $(".num2 option:selected").text();
    $(".wrong").html($wrong);
    
    $correct = parseInt($(".num1 option:selected").text()) + parseInt($(".num2 option:selected").text());
    $(".correct").html($correct.toString());
});