JSFiddle - React, Tailwind, and code Playground

HTML

<h2>£10 Each</h2>
<select name="iteam1" onChange="calc1()">
    <option value="10">1</option>
    <option value="20">2</option>
    <option value="30">3</option>
    <option value="40">4</option>
    <option value="50">5</option>
</select>

<div id="totalDiv1">&pound;
  <span id="totalDiv1Value">0</span>
</div>

<h2>£10 Each</h2>
<select name="iteam" onChange="calc()">
    <option value="10">1</option>
    <option value="20">2</option>
    <option value="30">3</option>
    <option value="40">4</option>
    <option value="50">5</option>
</select>

<div id="totalDiv">&pound;
  <span id="totalDivValue">0</span>
</div>
<br>
<h2>Total</h2>
<div id="totalall">&pound;0</div>

JavaScript

function calc() {
    var fruitOrVeg = document.getElementsByName("iteam")[0].value;
    var value = fruitOrVeg;
    document.getElementById("totalDivValue").innerHTML= value;
    total();
}



function calc1() {
    var fruitOrVeg = document.getElementsByName("iteam1")[0].value;
    var value = fruitOrVeg;
    document.getElementById("totalDiv1Value").innerHTML= value;
    total();
}

function total() {

    var y = parseInt(document.getElementById("totalDivValue").innerHTML);
    var z = parseInt(document.getElementById("totalDiv1Value").innerHTML);
    var x = y+z;
    document.getElementById("totalall").innerHTML = "£" + x;
}