This is a stepwise procedure to generate a random number within a given range in JavaScript.

var number = Math.random(); // generate a random decimal between 0 and 1
number *= 10; // scale the number so that it falls between the range 0 and 10 (or any number you'd like to make the max limit)
number = Math.ceil(number); // round the result up to the nearest whole number

You can combine this into one line to easily create a random number generator:

var number = Math.ceil(10 * Math.random());