cannot use + when try to add number

Question

After i selected option 1 and after i add the number like 100 it results like this 100100

This is the code:

var userAmount;
    var userMoney = 100;
         


        

Answer 1

That's because the user given number is actually a string.

A quick way to fix it is to type:

var totalMoney = userMoney + userAmount * 1;