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function MM_swapImgRestore() { //v3.0
  var i,x,a=document.MM_sr; for(i=0;a&&i<a.length&&(x=a[i])&&x.oSrc;i++) x.src=x.oSrc;
}

function MM_preloadImages() { //v3.0
  var d=document; if(d.images){ if(!d.MM_p) d.MM_p=new Array();
    var i,j=d.MM_p.length,a=MM_preloadImages.arguments; for(i=0; i<a.length; i++)
    if (a[i].indexOf("#")!=0){ d.MM_p[j]=new Image; d.MM_p[j++].src=a[i];}}
}

function MM_findObj(n, d) { //v4.0
  var p,i,x;  if(!d) d=document; if((p=n.indexOf("?"))>0&&parent.frames.length) {
    d=parent.frames[n.substring(p+1)].document; n=n.substring(0,p);}
  if(!(x=d[n])&&d.all) x=d.all[n]; for (i=0;!x&&i<d.forms.length;i++) x=d.forms[i][n];
  for(i=0;!x&&d.layers&&i<d.layers.length;i++) x=MM_findObj(n,d.layers[i].document);
  if(!x && document.getElementById) x=document.getElementById(n); return x;
}

function MM_swapImage() { //v3.0
  var i,j=0,x,a=MM_swapImage.arguments; document.MM_sr=new Array; for(i=0;i<(a.length-2);i+=3)
   if ((x=MM_findObj(a[i]))!=null){document.MM_sr[j++]=x; if(!x.oSrc) x.oSrc=x.src; x.src=a[i+2];}
}
var pTret = -1;
function parseText(v) {
	var w = "";
	var intpattern = /[^0-9]/;
	var decpattern = /[^0-9].[0-9]/;
	if (v == "") {
		return false;
	}
	if (!intpattern.test(v)) {
		pTret = parseInt(v) * 10;
		return true;
	}
	if (!decpattern.test(v)) {
		for (var i = 0; i < v.length - 2; i++) {
			w = w + v.charAt(i);
		}
		w = w + v.charAt(v.length - 1);
		pTret = parseInt(w);
		return true;
	}
	return false;
}
function clearAns(form) {
	form.petrol.value = "";
	form.lpg.value = "";
	form.saving.value = "";
}
function calcCost(form) {
	if (!parseText(form.mileage.value)) {
		clearAns(form);
		//error: please enter mileage, mpg & petrolPrice...
		return false;
	}
	var mileage = pTret;
	if (!parseText(form.mpg.value)) {
		clearAns(form);
		//error: please enter mileage, mpg & petrolPrice...
		return false;
	}
	var mpg = pTret;
	if (!parseText(form.petrolPrice.value)) {
		clearAns(form);
		//error: please enter mileage, mpg & petrolPrice...
		return false;
	}
	var petrolPrice = pTret;
	if (!parseText(form.lpg_price.value)) {
		clearAns(form);
		//error: please enter mileage, mpg & petrolPrice...
		return false;
	}
	var lpg_price = pTret;

	var petrol_cost = ((petrolPrice * 0.1) * 4.546) * ((mileage * 0.1) / (mpg * 0.1));
	var LPG_cost = ((lpg_price * 0.1) * 4.546) * ((mileage * 0.1) / ((mpg * 0.1) * 0.88));

	form.petrol.value = Math.ceil(petrol_cost) / 100;
	form.lpg.value = Math.ceil(LPG_cost) / 100;
	form.saving.value = Math.ceil(petrol_cost - LPG_cost) / 100;

	form.petrol.value = "£ "+form.petrol.value
	form.lpg.value = "£ "+form.lpg.value
	form.saving.value = "£ "+form.saving.value;
	return true;
}
function badValue(form) {
	alert("One or more values has been omitted or entered incorrectly.\nValues should either be integers or have a single number after the decimal point.");
}

function MM_openBrWindow(theURL,winName,features) { //v2.0
  window.open(theURL,winName,features);
}

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