Error "yum update" - Centos 7 - centos7

Question

When I tried use "yum update" I get these message:
Error: Multilib version problems found. This often means that the root
cause is something else and multilib version checking is just
pointing out that there is a problem. Eg.:
1. You have an upgrade for libstdc++ which is missing some
dependency that another package requires. Yum is trying to
solve this by installing an older version of libstdc++ of the
different architecture. If you exclude the bad architecture
yum will tell you what the root cause is (which package
requires what). You can try redoing the upgrade with
--exclude libstdc++.otherarch ... this should give you an error
message showing the root cause of the problem.
2. You have multiple architectures of libstdc++ installed, but
yum can only see an upgrade for one of those architectures.
If you don't want/need both architectures anymore then you
can remove the one with the missing update and everything
will work.
3. You have duplicate versions of libstdc++ installed already.
You can use "yum check" to get yum show these errors.
...you can also use --setopt=protected_multilib=false to remove
this checking, however this is almost never the correct thing to
do as something else is very likely to go wrong (often causing
much more problems).
Protected multilib versions: libstdc++-4.8.5-16.el7_4.1.i686 != libstdc++-4.8.5-16.el7.x86_64
Error: Protected multilib versions: libgcc-4.8.5-16.el7_4.1.i686 != libgcc-4.8.5-16.el7.x86_64
Error: Protected multilib versions: glibc-2.17-196.el7_4.2.i686 != glibc-2.17-196.el7.x86_64
Before this happened I had executed yum update but it never ended and I killed the pid of a stuck yum update with this command:
kill -9 2514

Answer 1

Try:
rpm --erase --nodeps libstdc++
yum install libstdc++
You need not re-install libstdc++.
Source: https://ask.fedoraproject.org/en/question/37518/cant-install-some-packages-yum-fails-with-multilib-error/
[EDIT]
For Error: ... Specifies Multiple Packages:
rpm -qa | grep -iE "libstdc++"
Here you must get multiple entries of libstdc++, then do:
rpm -e --allmatches libstdc++-4.8.5-16.el7 --nodeps
Do this recursively to resolve all the issues.
Source: https://ximunix.blogspot.in/2012/01/how-to-remove-packages-with-rpm-error.html