pg_ctl pointing postgres 9.5.4 after installation of postgres 10

I have updated postgres from 9.5.4 to the latest 10.4.

But after installation I am seeing 

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