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Start your free trial###### Dea Kristina

Courses Plus Student 1,792 Points# why +1?

Why do we have to add '+1' for the : Math.floor(Math.random() * xxx) + 1 ? Is it because we assume that it's a dice that has 1-6 values? If we don't assume a dice, can we just skip the +1 then? Thanks! :)

## 2 Answers

###### Steven Ang

41,749 PointsThe Math.floor will remove all the decimal places. Inside the Math.floor function, we use the Math.random to generate random numbers and multiplied it by 6 since it's a die. Remember that just solely using Math.random alone, we will always get numbers below 0 but not 1? That's why we plus it by 1 if we don't you will get numbers between 0 and 5.

###### Ruby Bassi

3,873 PointsI'm wondering the same thing: Is the +1 only relevant if using the die scenario?

###### jaspergradussen

5,876 Points+1 in Math.floor(Math.random() * xxx) + 1 is to be able to include the original input (being xxx). Say it where 10. I could never be randomly 10 because without +1 it would be a number between 0 and 9.

Because, Math.random() is a number between 0 and <1 and multiply that by 10, you never will be able to get the 10 (0.999999999 * 10 =NOT 10). Include Math.floor() and it makes sure that 9.99999 goes down to 9. So to make it reach 10 in the equation you add a +1.

###### Ruby Bassi

3,873 Pointsthat makes total sense. Thanks Jasper Gradussen!

## Dea Kristina

Courses Plus Student 1,792 Points## Dea Kristina

Courses Plus Student 1,792 PointsThanks! yeah I understand that, but this means that the +1 is because it assumes a dice with 6 values right :)