3 An average of 125 packets of information per minute arrive at an internet router. It takes an average of .002 second to process a packet of information. The router is designed to have a limited buffer to store waiting messages.

Any message that arrives when the buffer is full is lost to the system. Assuming that interarrival and service times are exponentially distributed, how big a buffer size is needed to ensure that at most 1 in a million messages is lost?