How to round the number up to 2 digits in Javascript

Sometimes you need to round up the number up to 2 digits. For example, you calculation has to show a result in currency.

There are two solutions to use on internet:

1) Use Math.random function.

var a=123.4567;

Math.random(a*100)/100

However, this is not really good, as for example in case of
var a=1.005;
Math.random(a*100)/100 results into 1 instead of 1.01.

2) use toFixed(2)

However, it is more secure option to use a.toFixed(2), which would return element as fixed 2 decimal value

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