Suppose users share a 3 mbps link. also suppose each user requires 150 kbps when transmitting, but each user transmits only 20 percent of the time, suppose packet switching is used and there are 225 users.

note: as we did in class use the binomial to normal distribution approximations (and the empirical rules µ±1σ =0.6826, µ ±2σ =0.9544, µ ±3σ =0.9973) to approximate your answer. (always draw the sketch of the normal distribution with the µ and σ)

find the probability that there are 63 or more users transmitting simultaneously