A formula for generating a random number within a given range using JavaScript is as follows:

Math.floor(Math.random() * (UpperRange - LowerRange + 1)) + LowerRange;

So to generate a random number between 25 and 75, the equation would be

Math.floor(Math.random() * (75-25+1)) + 25;

i.e.

Math.floor(Math.random() * 51) + 25;

Here’s the entire code:

<html xmlns="http://www.w3.org/1999/xhtml" >

<head>

<title>Random Number in JavaScript</title>

<script type="text/javascript">

var randomNumber = Math.floor(Math.random() * 51) + 25;

document.write("<p>" + randomNumber + "</p>");

</script>

</head>

<body>

</body>

</html>

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## 2 comments:

Thanks! What if I want it to be equal than or greater to X, but less than Y?

benjamin.morse.archer@gmail.com

Ben: In that case use the following:

Math.floor(Math.random()*(Y-X)) + X;

Although I have not tested it, but it should work!

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