Problems with installing Xcode on Mac 10.10.5 ( Locations - setting) I have followed the steps for the installation from www.instalrails.com . 
After installing Xcode they say to check the Preferences -> Location 
and have ensure you have the command line tools - Xcode 5.0.2 ( 5A3005 )
http://installrails.com/steps/install_xcode

But in my command line tools Xcode 7.1.1 (7B1005) appears and I cannot modify it.

I left it as it is and then tried to write this simple command in Terminal and it does not work :

$ jot - 1 25


It says command not found.

Can you please give some directions.
The linked picture in the install guide



is simply wrong. After installing the latest Xcode 7.1.1 the command line tools version is indeed Xcode 7.1.1 (7B1005).

jot is an executable (it prints sequential or random data) residing in /usr/bin. The purpose of executing jot - 1 25 is to ensure that the $PATH variable is set properly in your environment. If it can't be executed your $PATH variable probably doesn't include /usr/bin.

To get your current $PATH variable enter echo $PATH. The default $PATH in Yosemite looks like this:

/usr/local/bin:/usr/bin:/bin:/usr/sbin:/sbin


To restore the proper $PATH variable use one of the various answers here at apple.stackexchange.com.