9. In an automatic telegraph switching system incoming messages are stored in a queue until the retransmitting equipment of an outgoing trunk can send them. Messages arrive at the rate of 120 per hour. The times taken to retransmit messages may be assumed to have an exponential distribution with a mean time of 10 seconds. If the probability of losing a message because the store is full must be less than 10 6, how many messages must the equipment be able to store?

9. In an automatic telegraph switching system incoming messages are stored in a queue until the retransmitting equipment of an outgoing trunk can send them. Messages arrive at the rate of 120 per hour. The times taken to retransmit messages may be assumed to have an exponential distribution with a mean time of 10 seconds. If the probability of losing a message because the store is full must be less than 10 6, how many messages must the equipment be able to store?

EBK ELECTRICAL WIRING RESIDENTIAL

19th Edition

ISBN:9781337516549

Author:Simmons

Publisher:Simmons

Chapter6: Ground-fault Circuit Interrupters, Arc-fault Circuit Interrupters, Surge Protective Devices, Immersion Detection Circuit Interrupters, And Appliance Leakage Current Interrupters

Section: Chapter Questions

Problem 20R: Transients (surges) on a line can cause spikes or surges of energy that can damage delicate...

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