# Question: A lawyer has an unlisted number on which she receives

A lawyer has an unlisted number on which she receives on the average 2.1 calls every half– hour and a listed number on which she receives on the average 10.9 calls every half– hour. If it can be assumed that the numbers of calls that she receives on these phones are independent random variables having Poisson distributions, what are the probabilities that in half an hour she will receive altogether

(a) 14 calls;

(b) At most 6 calls?

(a) 14 calls;

(b) At most 6 calls?

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