Cant work out bug with my Javascript code

Question

I can't get the total price to show up on the screen. I am sure this is just a small bug somewhere but I can't find it.

var cabbage_prices = new Array();
cabbage_prices["Round6"]=20;
cabbage_prices["Round8"]=25;
cabbage_prices["Round10"]=35;
cabbage_prices["Round12"]=75;

var filling_prices= new Array();
filling_prices["None"]=0;
filling_prices["Lemon"]=5;
filling_prices["Custard"]=5;
filling_prices["Fudge"]=7;
filling_prices["Mocha"]=8;
filling_prices["Raspberry"]=10;
filling_prices["Pineapple"]=5;
filling_prices["Dobash"]=9;
filling_prices["Mint"]=5;
filling_prices["Cherry"]=5;
filling_prices["Apricot"]=8;
filling_prices["Buttercream"]=7;
filling_prices["Chocolate Mousse"]=12;


function getCabbageSizePrice()
{  
  var cabbageSizePrice=0;
  var theForm = document.forms["cabbageForm"];
  var selectedCabbage = theForm.elements["selectedcabbage"];
  for(var i = 0; i < selectedCabbage.length; i++)
  {
    if(selectedCabbage[i].checked)
    {
      cabbageSizePrice = cabbage_prices[selectedCabbage[i].value];
      break;
    }
  }
  return cabbageSizePrice;
}

function getFillingPrice()
{
  var cabbageFillingPrice=0;

  var theForm = document.forms["cabbageform"];
  var selectedFilling = theForm.elements["filling"];
  cabbageFillingPrice = filling_prices[selectedFilling.value];
  return cabbageFillingPrice;
}


function calculateTotal()
{
  var cabbagePrice = getCabbageSizePrice() + getFillingPrice();
  var divobj = document.getElementById('totalPrice');
  divobj.style.display='block';
  divobj.innerHTML = "Total Price For the Cabbage $"+cabbagePrice;

}

function hideTotal()
{
  var divobj = document.getElementById('totalPrice');
  divobj.style.display='none';
}

<div id="wrap">
  <form action="" id="cabbageform" onsubmit="return false;">
    <div>
      <div class="cont_order">
        <fieldset>
          <legend>Order Your Cabbages</legend>
          <label >Size of your Cabbage</label>
          <label class='radiolabel'><input type="radio"  name="selectedcabbage" value="Round6" onclick="calculateTotal()" />Round Cabbage 6" -  serves 3 people ($20)</label><br/>
          <label class='radiolabel'><input type="radio"  name="selectedcabbage" value="Round8" onclick="calculateTotal()" />Round Cabbage 8" - serves 5 people ($25)</label><br/>
          <label class='radiolabel'><input type="radio"  name="selectedcabbage" value="Round10" onclick="calculateTotal()" />Round Cabbage 10" - serves 10 people($35)</label><br/>
          <label class='radiolabel'><input type="radio"  name="selectedcabbage" value="Round12" onclick="calculateTotal()" />Round Cabbage 12" - serves 15 people($75)</label><br/>
          <br/>
          <label >Cabbage Filling</label>

          <select id="filling" name='filling' onchange="calculateTotal()">
            <option value="None">Select Filling</option>
            <option value="Lemon">Lemon Sauce($5)</option>
            <option value="Custard">Custard Sauce($5)</option>
            <option value="Fudge">Fudge Sauce($7)</option>
            <option value="Mocha">Mocha($8)</option>
            <option value="Raspberry">Raspberry($10)</option>
            <option value="Pineapple">Pineapple($5)</option>
            <option value="Dobash">Dobash($9)</option>
            <option value="Mint">Mint($5)</option>
            <option value="Cherry">Cherry($5)</option>
            <option value="Apricot">Apricot($8)</option>
            <option value="Buttercream">Buttercream($7)</option>
            <option value="Chocolate Mousse">Chocolate Mousse($12)</option>
          </select>
          <br/>            
        </fieldset>
      </div>

      <div class="cont_details">
        <fieldset>
          <legend>Contact Details</legend>
          <label for='name'>Name</label>
          <input type="text" id="name" name='name' />
          <br/>
          <label for='address'>Address</label>
          <input type="text" id="address" name='address' />
          <br/>
          <label for='phonenumber'>Phone Number</label>
          <input type="text"  id="phonenumber" name='phonenumber'/>
          <br/>
        </fieldset>
      </div>
      <input type='submit' id='submit' value='Submit' onclick="calculateTotal()" />
    </div>  
  </form>
</div>