[R] Install R on linux Mint

[John Sorkin]

I am trying to install R on Linux mint 17.1. I followed the instructions found on CRAN and got a messages about unmet dependencies. I detail below the steps I took:

I added deb http://lib.stat.cmu.edu/R/CRAN/bin/linux/ubuntu utopic/
to /etc/apt/sources.list
As can be seen below:

john-OptiPlex-GX270 apt # more sources.list
#deb cdrom:[Linux Mint 17.1 _Rebecca_ - Release i386 20141126]/ trusty contrib main non-free
deb http://lib.stat.cmu.edu/R/CRAN/bin/linux/ubuntu utopic/

And then followed the instructions on CRAN:

sudo apt-get update
AND RECEIVED THE FOLLOWING MESSAGE:

Fetched 316 kB in 8s (39.5 kB/s)                                               
Reading package lists... Done
W: GPG error: http://lib.stat.cmu.edu utopic/ Release: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 51716619E084DAB9

sudo apt-get install r-base
AND RECEIVED THE FOLLOWING MESSAGE:

The following packages have unmet dependencies:
 r-base : Depends: r-base-core (>= 3.1.2-1utopic0) but 3.0.2-1ubuntu1 is to be installed
          Depends: r-recommended (= 3.1.2-1utopic0) but it is not going to be installed
E: Unable to correct problems, you have held broken packages.

John David Sorkin M.D., Ph.D.
Professor of Medicine
Chief, Biostatistics and Informatics
University of Maryland School of Medicine Division of Gerontology and Geriatric Medicine
Baltimore VA Medical Center
10 North Greene Street
GRECC (BT/18/GR)
Baltimore, MD 21201-1524
(Phone) 410-605-7119
(Fax) 410-605-7913 (Please call phone number above prior to faxing) 

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