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JavaScript JavaScript Basics (Retired) Working With Numbers The Random Challenge Solution

Vic Mercier
Vic Mercier
3,276 Points
Posted by Vic Mercier
Vic Mercier
3,276 Points

math.floor(math.random()*random1-random2+1)+random1;

I don't know why we add +random1 at the end of the syntax.

Nadav Reis
Nadav Reis
5,561 Points

I believe that without the +random1 at the end, the number would be outside of the range.

Imagine is your numbers were 75 and 100. The difference is 25.

You would get something like .82929299 * 25 + 1

The result is not between 75 and 100. If you add 75 back in (ie, add random1), your number will be between 75 and 100.

1 Answer

Steven Parker
Steven Parker
231,271 Points
Steven Parker
Steven Parker
231,271 Points

That's the way the formula for a random pick works.

The formula is: "(random * range) + minimum" where range is: "maximum - minimum + 1".

But that would mean your numbers are out of order, plus you need parentheses to override the operator precedence. So your code should probably be:

math.floor(math.random() * (random2 - random1 + 1)) + random1;