On the Admin Panel Dashboard, you can find a box called "Right Now". There you can see the version of the WordPress installation. I have seen this result in WordPress
3.2.1. You can also see this in version
In WP Version 3.8.3
In WP Version 3.9.1 Admin Side, You can see the version by clicking the WP logo which is located at the left-top position.
You can use
In the WordPress Admin Footer at the Right side, you will see the version info(Version 3.9.1).
You can get the WordPress version using the following code:
<?php bloginfo('version'); ?>
The below file is having all version details
Update for WP 4.1.5
In WP 4.1.5, If it was the latest WP version in the footer right part, it will show the version as it is. If not, it will show the latest WP version with the link to update.
Check the below screenshot.