# Question: In Exercise 4 90 let the transmission time be Tt seconds

In Exercise 4.90 let the transmission time be Tt seconds for a packet. If the packet was received incorrectly, then a message is sent back to the transmitter that states that the message was received incorrectly. Let the time for sending such a message be Ti. Assume that if the packet is received correctly that we do not send an acknowledgement. What is the average time for a successful transmission?

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