A circuit-switching scenario in whichNcs users, each requiring a bandwidth of 25 Mbps, must share a link of capacity 150 Mbps.
A packet-switching scenario withNps users sharing a 150 Mbps link, where each user again requires 25 Mbps when transmitting, but only needs to transmit 10 percent of the time.

What is the probability that a given (specific) user is transmitting, and the remaining users are not transmitting?