install opencv 2.4.13

I am using ODROID (arm board) with Ubuntu 14.04 and initial installed Opencv 2.4.8. And I want use to the newest version which is 2.4.13. I followed the [tutorial](http://docs.opencv.org/2.4/doc/tutorials/introduction/linux_install/linux_install.html) step by step. But when I run the command **pkg-config --modversion opencv**, the output is still 2.4.8. I have a question how to upgrade opencv to newest version? Or how I can set the libs path to find this package? Or how to uninstall the previous one? Thanks for your help.