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   var original=28.453
1) //round "original" to two decimals
var result=Math.round(original*100)/100;  //returns 28.45
2) // round "original" to 1 decimal
var result=Math.round(original*10)/10;  //returns 28.5
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3) //round "original" to two decimals
var result=original.toFixed(2); //returns 28.45
4) // round "original" to 1 decimal
var result=original.toFixed(1); //returns 28.5
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function roundNumber(number,decimals) {
var newString;// The new rounded number
decimals = Number(decimals);
if (decimals < 1) {
newString = (Math.round(number)).toString();
} else {
var numString = number.toString();
if (numString.lastIndexOf(".") == -1) {// If there is no decimal point
numString += ".";// give it one at the end
}
var cutoff = numString.lastIndexOf(".") + decimals;// The point at which to truncate the number
var d1 = Number(numString.substring(cutoff,cutoff+1));// The value of the last decimal place that we'll end up with
var d2 = Number(numString.substring(cutoff+1,cutoff+2));// The next decimal, after the last one we want
if (d2 >= 5) {// Do we need to round up at all? If not, the string will just be truncated
if (d1 == 9 && cutoff > 0) {// If the last digit is 9, find a new cutoff point
while (cutoff > 0 && (d1 == 9 || isNaN(d1))) {
if (d1 != ".") {
cutoff -= 1;
d1 = Number(numString.substring(cutoff,cutoff+1));
} else {
cutoff -= 1;
}
}
}
d1 += 1;
}
if (d1 == 10) {
numString = numString.substring(0, numString.lastIndexOf("."));
var roundedNu