<script>
function formatNumber(number, decimalPlaces)
{
var coeff = Math.pow(10, decimalPlaces);
return Math.round(number * coeff) / coeff;
}
var pi = 3.14159265;
document.write('Though the value of PI is actually ' + pi + ', most people only remeber it to be ' + formatNumber(pi, 2) + '.');
</script>