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

John Bamberg
John Bamberg
9,774 Points
Posted by John Bamberg
John Bamberg
9,774 Points

If 1 is added to the end? How to I return 1?

Math.floor( Math.random() * 6 ) + 1

If 1 is added to the end of the statement. How will I ever return 1?

2 Answers

Ted Sumner
PLUS
Ted Sumner
Courses Plus Student 17,967 Points
Ted Sumner
Ted Sumner
Courses Plus Student 17,967 Points

Random numbers return a value between 0 and 1. The floor function rounds down. Without the 1, you get values between 0 and 5, thus you need a +1 to get between 1 and 6.

Ted Sumner
Ted Sumner
Courses Plus Student 17,967 Points

The Math.floor() function returns the largest integer less than or equal to a given number.

Iain Simmons
MOD
Iain Simmons
Treehouse Moderator 32,305 Points
Iain Simmons
Iain Simmons
Treehouse Moderator 32,305 Points

Or another way to look at it, if Math.random() returns anything less than 1/6 (0.1666666666... etc), that will be multiplied by 6 and still be equal to a value less than 1. That will be 'floored' to 0, so you add the 1 to it to get 1.

Not sure if that makes any more sense than the way it was already explained...

You could always store the random number in a variable and then perform the operations on it one-by-one and print out the result at each step if you'd like to see how it all works.