title: issue with adding values from array
body: <p>I am writing a small application for the user to enter the name of a book and then its price, push the values of those to an array, output the book name and cost to the page and then display the total.</p>
  
  <p>the issue I am having is with the total, for example:</p>
  
  <p>If I write 2 as the value of each of the values, the "totalOutput" says 022222 instead of 10 as I would expect, I have tried a few different things and read a few articles on here but haven't found any to be much help or that useful.</p>
  
  <p>these are the exact lines I am having issues with:</p>
  
  <pre><code>//go over each item in price and add up the total
          price.forEach(function addNumber(value) {
              total += value;
          });
  
  //write the total
      totalOutput.innerHTML = "the total value of the books is " + total;
  }
  </code></pre>
  
  <p>And incase you need it - here is my full javascript code:</p>
  
  <pre><code>//Book shop task
  function trackBooks() {
  
      //target the output ul and store in a variable
      var output = document.getElementById("booksOutput");
  
      //Setup the two arrays to hold the book names and their prices.
      var books = [];
      var price = [];
  
      //declare a variable for working out the total
      var total = 0;
  
      //target the total output
      var totalOutput = document.getElementById("totalOutput");
  
      //set up a counter for the loop
      var x = 0;
  
      //setup the loop for entering the names of the books and their prices, for the sample, I have set the loop to run 5 times as stated in the pseudo code
      for (var i = 0; i &lt; 5; i++) {
  
          //add one to the counter on each loop
          x = x + 1;
  
          //declare a variable to ask the user for the book name and the cost and push those values to their arrays we created above
          var bookName = prompt("enter book name number " + x);
          books.push(bookName);
          var bookPrice = prompt("how much does book number " + x + " cost?");
          price.push(bookPrice);
  
          //create a variable to create new li tags on output 
          var newLi = document.createElement("li");
  
          //add the required info to the new link
          newLi.innerHTML = "book " + x + ": " + "&lt;strong&gt;" + books[i] + "&lt;/strong&gt;" + " costs " + "&lt;strong&gt;" + price[i] + "&lt;/strong&gt;";
  
          //write out the name and price to the page
          output.appendChild(newLi);
  
      }
  
      //go over each item in price and add up the total
      price.forEach(function addNumber(value) {
          total += value;
      });
  
      //write the total
      totalOutput.innerHTML = "the total value of the books is " + total;
  }
  </code></pre>