JSFiddle - React, Tailwind, and code Playground

by jnfsmile

HTML

<select id="VatExpense">
        <option data-rate="20" value="" disabled selected>Expense Type</option>
        <option data-rate="20" value="0">Telephone</option>
        <option data-rate="0" value="1">Public Transport & Taxis</option>
        <option data-rate="20" value="0">Computer Consumables</option>
        <option data-rate="20" value="0">Subsistence</option>
        <option data-rate="0" value="1">Overseas Travel</option>
    </select>

   <input type="text" id="vat" placeholder="Rate">

JavaScript

$("#VatExpense").change(function(){
    $("#vat").attr("placeholder", $(this).find(":selected").data("rate") + "%");
})