Please help with this simple java script code

[Gecco]

Here's what I need to do:
Delivery is charged @ 1£ per mile above 3 miles

if (distance is less than 3 miles)
Inform of free delivery
else
If (distance is between 3 and 12 miles)
Inform of delivery charge
else
Inform of maximum delivery distance 12 miles

<SCRIPT LANGUAGE = "JavaScript">

// A delivery charge program 

var distance;
var extraDistance; 

distance = window.prompt('Please enter the distance in miles', '');
distance = parseFloat(distance);




if (distance <= 3)
{
	document.write('You qualify for free delivery');
}
extraDistance = distance - 3
else
 if (distance  > 3 && <= 12);
  {      
    document.write(' You will be charged ' + extraDistance + '£');
}
else 
  {        
    document.write('Our maximum delivery distance is 12 miles!');
}

</SCRIPT>

I don't know where i have gone wrong. Your help is greatly appreciated.

 

[Gecco]

Thank you very much for the quick reply.