Number.prototype.toPercent = function(n){n = n || 0;return ( Math.round( this * Math.pow( 10, n + 2 ) ) / Math.pow( 10, n ) ).toFixed( n ) + '%';}
var A=0.358975, B=0.25554;
?alert([A, A.toPercent(3), B, B.toPercent()].join('\n'));