Assignment task: Your friendly Eng 1000 professor receives 200 non-spam emails every day on average. He estimates that of these, 50 need a reply. Over a period of time, he finds that the average number of unanswered emails in his inbox that still need a reply is 100.
a. On average, how much time does it take for the professor to send a reply to an email that needs a response?
b. On average, ENG1000 constitutes 25% of his emails that require a reply. He responds to each ENG1000 email in 60 minutes, on average. How much time on average does it take him to send a reply to any non-ENG1000 email?