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JavaScript

Don't understand Math.floor / Math.random

I don't understand why we multiply by 6 here in order to have a number between 1 and 6. I know that Math.random is from 0 to 1 except 1 and math.floor rounds floats to interigers but don't get where the *6 is from.

var randomNumber = Math.floor(Math.random() * 6) + 1;

1 Answer

Hi, you can take 6 as a value u want to multiple your outcome of Math.random(), e.g if you want a given month, and you know months in a year are 12, so you can do

var randomMonth = Math.floor(Math.random() * 12) + 1;

and each time you call it, you will get a randomMonth between 0 to 11, and you add + 1 to make it a 12. Basically it is what you want that result of Math.random to multiplied with.

Hope it helps.