I've two functions that return an integer finSum() and getTotal().
How do I sum the result and send it to <div class="grandTotal"></div> using something like $(".grandTotal").text(somevalue);.
Arrow functions provide an implicit return: values are returned without the usage of the return keyword.
You can use template literals to show your result on div.
Here is a full example using arrow function and template literals.
let a = 2,
b = 3,
c = 4,
d = 5
const finSum = () => a + b;
const getTotal = () => c + d;
const grandTotal = () => finSum() + getTotal();
let html = `<span>Gand Total: ${grandTotal()}</span>`;
$('.grandTotal').html(html);
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<div class="grandTotal">
</div>
Just add the two returned values together:
var somevalue = finSum() + getTotal();
$(".grandTotal").text(somevalue);