function total_ht(montantht)
{
	document.form_contact.total.value=montantht+'.00';
	document.form_contact.ch_table.checked=false;
	calcul_montant(montantht);
	reduct();
}

function calcul_montant(montantht)
{
	tva=(Math.round(19.60*montantht))/100;
	if((Math.round(tva*10))==(tva*10))
		tva+='0';

	document.form_contact.tva.value=tva;
	
	ttc=parseFloat(parseFloat(tva)+parseInt(montantht));
	if((Math.round(ttc*10))==(ttc*10))
		ttc+='0';

	document.form_contact.totalttc.value=ttc;
	
	document.form_contact.acompte.value=Math.round((30*ttc)/100)+'.00';
}

function ajout_mobilier()
{
	if((document.form_contact.ch_table.checked==false)||(document.form_contact.total.value==''))
	{
		total_ht(0);
	}
	else
	{
		montant_avant=parseInt(document.form_contact.total.value);
		nouveau_montant=80+montant_avant;
		document.form_contact.total.value=nouveau_montant+'.00';
		montantht=nouveau_montant;
		calcul_montant(montantht);
	}
	reduct();
}