I have domain xyz.com its pr#3 , i wish to start new website/blog . Will adding a subdomain pqr.xyz will be any good for it ? will google weigh it?
you need to understand the use of sub-domain. it should be used when you have completely different content from the original domain and is too large to be used on the man domain like blog or a forum. moreover, if you want that new content to be known by the present brand name, then use a sub-domain