JSFiddle - React, Tailwind, and code Playground

HTML

<p>Labour cost: <input type="text" id="labor_cost" /></p>
<p>Other cost: <input type="text" id="other_cost" /></p>
<p>Profit Value: <input type="text" id="profitValue" /></p>
<p>Product Total Cost: <input type="text" id="productTotalcost" /></p>
<button id="submit">click</button>

<hr/>
<p>Show Proposed Price: <span id="showproposedprice"></span></p>
<p>Proposed Price: <input type="text" id="proposedprice" /></p>

JavaScript

$("#submit").click(function() {
    var labor_cost = Number($("#labor_cost").val());
    var other_cost = Number($("#other_cost").val());
    var profitValue = Number($("#profitValue").val());
    var ingCost = Number($("#productTotalcost").val());
    var profitAmount = ((ingCost+other_cost+labor_cost)*profitValue/100);
    $("#showproposedprice").html((ingCost+other_cost+labor_cost+Number(profitAmount)).toFixed(2));                                                    
    $("#proposedprice").val((ingCost+other_cost+labor_cost+Number(profitAmount)).toFixed(4));
})