Since Systemd was enabled by default on Linux Mint, timedatectl / timesyncd (part of systemd) replaced most of the funtionality of ntpdate / ntp. timesyncd is available by default and replaces not only ntpdate, but also the client portion of ntp. timesyncd will keep your Mint workstation time in sync. Try the command $timedatectl status for a confidence check.
this is an essential component in the OS. Am surprised it wasn't installed by default.
This should be a default install and is not...unlike a lot of other silly junk that is.