Is it possible that we have one domain where database and site is hosted on the single dedicated IP. If we wish to host domains subdomain on another dedicated IP address and use the domains databse to display quotes. Will it be done or not. Or we have to host the subdomain also in same domain with same IP address?
Yes. surely different domains/subdomains can be assigned to different servers/IPs and surely you can access a database remotely from a separate machine. Your primary site and the one that your subdomain refers to can be served by a single database residing on the primary site's machine.
Yes, you can host a site and a database on the same domain name and the same IP. If they are separate servers, you need a router so that it can route different ports to separate local IP addresses.
Yes, you can have a subdomain on a different IP, and you can access the database either from the outside (public / separate local net) or from the same local net. You can have a separate IP for the subcomain even if you use the same router and put the server in the same local net.