javascript round to nearest 10

1Math.round(X);           // round X to an integer
2Math.round(10*X)/10;     // round X to tenths
3Math.round(100*X)/100;   // round X to hundredths
4Math.round(1000*X)/1000; // round X to thousandths

1var rounded = Math.round(number / 10) * 10

1function round5(x)
2{
3    return Math.ceil(x/5)*5;
4}
5

1round(12345.6789, 2) // 12345.68
2round(12345.6789, 1) // 12345.7

1function round(value, precision) {
2    var multiplier = Math.pow(10, precision || 0);
3    return Math.round(value * multiplier) / multiplier;
4}

1function round100 (num1) {
2    return Math.round(num1/100)*100;
3}