Why is this code displaying NaN as output?

Question

https://code.sololearn.com/WthMfWpY8df6/?ref=app

Answer 1

function multiply() should not have those parameters. Remove them. The reason for NaN is that you were using the variable a and b in the function scope (those are not from the prompt) . As those variables haven't been initiazed the expression happens like this.
var c = a*b
= undefined*undefined
= null

Answer 2

Also, var c = a*b instead of var c = document.write(a*b);

Answer 3

Coder What's the advantage of storing the call to document.write in a variable? Doesn't make sense to me 🤔

Answer 4

Satya Routray Anna said that because c will store undefined as document.write method returns nothing instead of a*b as you want.

Answer 5

Nothing…
And I don't think this is going to work… it'll return undefined😀

edit: What is the use of var c? (after you edited) Scrap it. Coder

Answer 6

Anna why ?