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

Sean Flanagan
Sean Flanagan
33,235 Points
Posted by Sean Flanagan
Sean Flanagan
33,235 Points

I generated a number outside the range

Hi.

How did I end up with "30 is a number between 5 and 29"?

HTML:

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <link rel="stylesheet" href="css/main.css">
  <title>JavaScript Basics</title>
 </head>
<body>
  <div class="container">
  <h1>Random Number Generator</h1>
   <script src="random.js"></script> 
  </div>
</body>
</html>

JavaScript:

var input1 = prompt("Please type a starting number");
var bottomNumber = parseInt(input1);
var input = prompt("Please type a number");
var topNumber = parseInt(input);
var randomNumber = Math.floor(Math.random() * (topNumber - bottomNumber + 1)) + 1 + bottomNumber;
var message = "<p>" + randomNumber + " is a number between " + bottomNumber + " and " + topNumber + ".</p>";
document.write(message);

Thanks.

Sean

Sean Flanagan
Sean Flanagan
33,235 Points
Sean Flanagan
Sean Flanagan
33,235 Points

Thanks again Amy!

Sean :-)

1 Answer

Amy Rutherford
Amy Rutherford
9,659 Points 
var randomNumber = Math.floor(Math.random() * (topNumber - bottomNumber + 1)) + bottomNumber;

The second + 1 isn't needed.