I'm almost afraid to ask...

    The + 1 in line 6 of the double generator goes inside the parenthesis
     why is it different though the concept for the codes seems to be the same

<li>code for the single generator</li>

<pre>
var userInput = prompt('pick a number from 1 to ~');
var userNumber = parseInt(userInput);
var randomNumber = Math.floor(Math.random() * userNumber) + 1;  
alert( randomNumber + ' is a number between 1 and ' + userNumber);
</pre>
<li>code for double generator</li>
<pre>
var userInput1 = prompt('pick a low number');
var lowNumber = parseInt(userInput1);
var userInput2 = prompt('pick a high number');
var highNumber = parseInt(userInput2);
var randomNumber = Math.floor(Math.random() * (highNumber -
lowNumber + 1 ) + lowNumber);
alert(randomNumber + ' is a number between 1 and ' + highNumber );
</pre>