Don has a Company named "D Bhai Kidnapping & Murder Private Limited." He has to threat 10 people per day over Telephone. 40% of the people he threats are cinema stars in Mumbai, 30% are businessman in Delhi, 20% are businessmen in Chennai and 10% are shopkeepers in Kolkatta. If ISD charges are Rupees 15, 25, 40, 50 per minute from Dons city Islamabad to Mumbai, Delhi, Kolkatta and Chennai respectively and he gets a Telephone bill of Rupees 10,230/- in a month, find out the number of cinema stars in Mumbai, threatened in that particular month.