Premium of .74% doesn’t always mean a good buy. It depends on market conditions, number of days left for expiry , sector trend in general, any major policy announcements etc. among many other factors. Apply your discretion and study well before making a buy/sell .
The calculation does NOT mean ‘CE price SHOULD BE 190’. It rather specifies that you have a chance to make profit only if the index moves up by 190 points or more.