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JavaScript JavaScript Basics (Retired) Working With Numbers Create a random number

Posted by Wuen Han Lee
Wuen Han Lee
Courses Plus Student 2,305 Points

Dave, can Math.random() yield 1? If it can, then we might get 7 from Math.floor(Math.random()*6) + 1 right?

I hope some one can help me clarify this, thanks in advance!

5 Answers

Sergey Podgornyy
Sergey Podgornyy
20,660 Points
Sergey Podgornyy
Sergey Podgornyy
20,660 Points

The random() method returns a random number from 0 (inclusive) up to but not including 1 (exclusive). The floor() method rounds a number downwards to the nearest integer, and returns the result.

So when you create random number, you will receive value 0-1. Then you need to multiply on 7 and then add 1 (if you want random number 0-7), because floor will rounds a number downwards.

Ferdinand Pretorius
Ferdinand Pretorius
18,705 Points
Ferdinand Pretorius
Ferdinand Pretorius
18,705 Points

Hi Wuen Han Lee,

Math.random will return a floating-point random number between 0 and 1 , but NOT including 1 itself.

Jacob Mishkin
Jacob Mishkin
23,117 Points
Jacob Mishkin
Jacob Mishkin
23,117 Points

Sergey Podgornyy is correct.

Wuen Han Lee
PLUS
Wuen Han Lee
Courses Plus Student 2,305 Points
Wuen Han Lee
Wuen Han Lee
Courses Plus Student 2,305 Points

Ok, I found the answer :" // Returns a random number between 0 (inclusive) and 1 (exclusive)"

Jacob Mishkin
Jacob Mishkin
23,117 Points

I would suggest playing around with Math.random. there is a lot of fun things you can do with it. I would first suggest playing with rgb colors! See if you can make a div change colors by using the math.random and the CSS transition property. Or make multiple divs with different colors. There is a lot you can do with it.

Wuen Han Lee
PLUS
Wuen Han Lee
Courses Plus Student 2,305 Points
Wuen Han Lee
Wuen Han Lee
Courses Plus Student 2,305 Points

Thanks Sergey, Ferdinand and Jacob for the prompt replies. You guys are amazing!