To get the tourist Visa, is it necessary that 5 persons should apply together?

Dear Sir, my wife, sister-in-low and my self are hoping to visit PRC for a few days.We have heard that it is necessary less than five people should apply together to get the L type. Is it true? We have visited England,India And Japan (Three times to Japan).We like to visit your beautiful country too.We can get other relevant documents including hotel bookings but please let me know about necessary documents too. So please advice me to get the L type for 3 of us. Thank you very much, have a nice day. (Sarath Edirisooriya. September 15, 2013)