Sorry, may be I could not make myself clear. I know how to change the currency settings and the currency scope. My base currency is USD. But, when I make purchase from NPR store, the "Grand total to be charged" (please refer to the snapshot in my question) displays in USD where as its supposed to be NPR(since the purchase is made from NPR store).

@NasirPerwaiz Thanks for the reply. When I set the price scope to Global (not website) it worked!

@AmitBera Kindly refer to my previous comment.

@NasirPerwaiz I have loaded the websites and appropriate currency is also displayed. But the problem is, if the price of a product is NRS 70,000 in NRS website then the price remains same in USD website and is displayed 70,000 USD. The auto conversion is not working or may be I am unaware of how to do it. Could you please suggest something?

I guess the query should be "WHERE value LIKE" instead of "WHERE path LIKE". The values are intact in core_config_data table. Furthermore, I am accessing the live site using FTP and I dont have access to the server root. Is there any way I can manage it?