LaTeX: How to install TeX Live - qtree package in Ubuntu 12.10

There is a question on TeX - StackExchange that has no direct solution to the installation of the qtree - TeX Live package in Ubuntu. And I want to answer that in this post, then just drop the link of this article to the comment section of the said query. So here is what I did:

1. Open the Ubuntu Dash, and search for Ubuntu Software Center;
   
2. In the Software Center, search for qtree;
   
3. Select the first entry (Humanities Packages), and click on More Info to confirm if qtree is indeed included in this item;
4. Finally, click .

There you go, you can try it now. Here is a simple Statistics problem from Elementary Statistics Book of MSU-IIT Department of Mathematics and Statistics that uses tree diagram,
 
Problem: Three items are selected randomly from a manufacturing process. Each item is inspected and classified as Defective (D) or Non-defective (N). Determine the number of ways this selection can be done using the tree diagram.

Solution:

There are 8 ways this selection can be done.

Below is the $\mathrm{\LaTeX}$ code of the above tree diagram,

I never tried, but I think the above method also works on recent versions of Ubuntu.