$ sudo apt-get update
$ sudo apt-get install qtdeclarative5-examples 

qtdeclarative5-examples is installed in your system.

Make ensure the qtdeclarative5-examples package were installed using the commands given below,

$ sudo dpkg-query -l | grep qtdeclarative5-examples *

You will get with qtdeclarative5-examples package name, version, architecture and description in a table

qtdeclarative5-examples package basic information: