function  doMath()

{

var pag=window.document.quoteme.pages.value; // number of pages
var size=window.document.quoteme.book_size.selectedIndex; // book size selected // 1=A4, 2=A5
var numb=window.document.quoteme.book_number.value; // number of books required
var monoa5=0.01; // price per page mono A5
var monoa4=0.02; // price per page mono A4
var covera5=1.3; // price per cover a5
var covera4=1.9; // price per cover a4
var micron=0.053 // micron multiplier for spine width
var q; // total cost of books
var spine; // spine result at PrintonDemand prices

  

 
if (numb<1)

 {

		alert ("Please enter a quantity"); return false; // Book quantity is below minimum

 }

if (pag==0)

 {

		alert ("Please enter the number of pages"); return false; // number of pages have not been entered

 }

	if (size==[0])

 {

		alert("Please choose a book size"); return false; // Book size has not been selected

 }

 	

	if(size==[1])

 {

 var q = ((pag * monoa4) + covera4) * numb; // calculate price of A4

 }

	if (size==[2])

 {

var q = ((pag * monoa5) + covera5) * numb; // calculate price of A5

 }



	

q=Math.ceil(q);

var spine = pag*micron;

window.document.quoteme.spineoutput.value=spine;

window.document.quoteme.cost.value=q;

}