USD=4.2;

function Yo2Grv(yo)
{	x=USD*yo*100;
	x=Math.ceil(x);
	grn=Math.floor(x/100); kop=x-grn*100
	if ( kop == 0 ) {
		document.write(grn+",00");
	} else if (kop < 10 ){
		document.write(grn+",0"+kop);
	} else {
		document.write(grn+","+kop);
	}
}

function Yo2GrvRound(yo)
{	x=USD*yo;
	x=Math.round(x);
		document.write(x+" грн.");
}

function Yo2GrvRound2(yo)
{	x=USD*yo;
	x=10*Math.round(x/10);
		document.write(x+" грн.");
}