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![andres ponton](https://secure.gravatar.com/avatar/5cdb7bc66f0bacba187deed9ca623eac?s=96&d=https%3A%2F%2Fecs-static.teamtreehouse.com%2Fassets%2Fcontent%2Fdefault_avatar-445fbbabfc8dc9188fb5967fe43322ee0c3e0dd1e10f378bf8343784af5a13eb.webp&r=pg)
andres ponton
10,350 Points1. Why does he use floor instead of round 2. in the second challenge why does he add the +1
I understand that you have to add a 1 in case the random number is 0. but in this case I dont understand why he adds the 1 after the substraction.
1 Answer
![Dane Parchment](https://uploads.teamtreehouse.com/production/profile-photos/352832/micro_Dane_s_Profile_Photo_Cropped.jpg)
Dane Parchment
Treehouse Moderator 11,076 PointsHe uses floor
because it rounds down, that way we don't get a potentially larger number than the range of values we want generated. Round
will round up so it is not a good choice since it will potentially do what we mentioned above and provide larger values.
The addition actually happens before the subtraction, this is more of a math thing, but remember your order of operations (PEMDAS)? Addition will always be evaluated before subtraction.
Hope that helps.