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JavaScript

Why use math.floor(math.random()*6)+1 instead of math.ceil()?

I couldn't understand the video's explanation. The video say using math.ceil have chance of giving me value from 0 - 6.

Whether I use math.floor() or math.ceil() method, if math.random generates 0, then wouldn't I still get 0?

2 Answers

Jason Anders
MOD
Jason Anders
Treehouse Moderator 145,863 Points

Hi SeHyun Choi

While it may generate zero, that is why you are adding 1 after the .random() method is called. This way you will always have a range of 1 - 6.9999... (in this example). Because you can have a float that is greater than 6, you'll want to use .floor() to maintain the absolution of the 1 -6 range you are looking for. If you use `.ceil() you run a possibility that it will return a 7.

Hope that clears it up for you. :) :dizzy:

Thank you!