function sum() {
var nResult = 0;
for (var i = 0, l = arguments.length; i < l; i++) {
nResult += (!isNaN(arguments[i]) && window.parseFloat(arguments[i]))||0;
}
return nResult.toFixed(3) * 1000 / 1000;
}
document.write(sum(1, '2', 3, 4, 5,null,false,true,'A','1.000017654788','0.1','0.2'));
console.log((0.1+0.2005).toFixed(3)*1000/1000);
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