pg_ctl pointing postgres 9.5.4 after installation of postgres 10

Hi

I have updated postgres from 9.5.4 to the latest 10.4.

But after installation I am seeing

support(at)platform1:/usr/bin$ ls -lah pg_ctl
lrwxrwxrwx 1 root root 34 Jun 13 08:59 pg_ctl ->
/usr/lib/postgresql/9.5/bin/pg_ctl

The issue appears similiar to the one discussed here
https://stackoverflow.com/a/24763074/785523.

To install postgres 10 I have followed the below steps:-

sudo add-apt-repository "deb http://apt.postgresql.org/pub/repos/apt/
trusty-pgdg main"

wget --quiet -O - https://www.postgresql.org/media/keys/ACCC4CF8.asc |
sudo apt-key add -

sudo apt-get update

sudo apt-get install postgresql-10

Then performed the data migration using pg_upgrade and then
removed postgres 9.5

Now posgres -V is also failing with the below error

support(at)platform1:/usr/bin$ postgres -V
The program 'postgres' is currently not installed. You can install it by
typing:
sudo apt-get install postgres-xc

Can someone let me know what is wrong and how can I fix it?