Hi, im having some issues with the following question.

Question) A sales manager receives 6 phone calls on average between 9.30am and 10.30am on a weekday. Find the probability that during a 5 day working week, there will be exactly 3 days on which she receives no calls between 10am and 10.10am.

X ~ Po(6) for a single day. Am i correct in assuming i should be using nCr to determine the possible combination of 3 days in 5. I tried to multiple this by the probability of no calls for a single day ie X ~ Po(1) due to the fact that the time period is 1/6 that originally stated but didnt get the correct answer.

correct answer is 0.199 btw

Any help would be appreciated.

Thanks

Question) A sales manager receives 6 phone calls on average between 9.30am and 10.30am on a weekday. Find the probability that during a 5 day working week, there will be exactly 3 days on which she receives no calls between 10am and 10.10am.

X ~ Po(6) for a single day. Am i correct in assuming i should be using nCr to determine the possible combination of 3 days in 5. I tried to multiple this by the probability of no calls for a single day ie X ~ Po(1) due to the fact that the time period is 1/6 that originally stated but didnt get the correct answer.

correct answer is 0.199 btw

Any help would be appreciated.

Thanks

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