# Probability Questions

Someone help me, please note that options are four but go ahead n solve (post workings please) Telephone calls arrive at the rate of 48 per hour at the reservation desk for Regional Airways. a. Find the probability of receiving 3 calls in a 5 minute interval. Choose one answer. a. 62.88% b. 19.54% c. 43.35% d. 56.65% b. Find the probability of receiving 10 calls in 15 minutes. Choose one answer. a. 5.29% b. 15.60% c. 97.42% d. 10.48% c. Suppose that no calls are currently on hold. If the agent takes 5 minutes to complete processing the current call, what is the probability that no callers will be waiting on hold? Choose one answer. a. 1.83% b. 0.67% c. 9.07% d. 4.98% d. If no calls are currently being processed, what is the probability the agent can take 3 minutes of personal time without being interrupted? Choose one answer. a. 9.07% b. 1.83% c. 0% d. 0.67%

b d a a do you have the answers? if you do, let me know, then i will post the workings…

dont have the answers they aint in Qbank or CFAI text…

where did you get them from?

48 calls per hour => 48 calls in 60 min => r= 48/60 In these types of problems Poisson distribution is applied i) 3 calls in 5 min interval Prob =[(rT)^k] * e(-rT) /k!; r=48/60=4/5; T=5; k=3; plug these in the Prob formula to get Prob = 19.54% ii) 10 calls in 15 mins solve as in part i with r=48/60=4/5; T=15; k=10; Prob= 10.48 % ; iii) No callers waiting on hold in next 5 min means that you need to find the probability that no new calls will coem in next 5 min so r=48/60=4/5; T=5; k=0; Prob= 1.83% remember the fact that 0!=1;(zero factorial is always 1) iv) agent can take 3 min of personal tiem if he does not recieve any calls in next 3 min so r=48/60; T=3; k=0; Prob=9.07%; I have solved your homework…

Thanks gauri…you did just that…back to the L2 forum now!!

Semacks Wrote: ------------------------------------------------------- > Thanks gauri…you did just that…back to the L2 > forum now!! are you seriously in level2 … good luck!!

to confirm, these are not level 1 questions?

yeap…had tried to solve using the binomial with similar logic and got solutions very close for 8 n 9. Just a refresher which distribution is this?? PS: This stuff aint on the curriculum…just jogging my quant appetite

gauri…hadn’t seen the Poisson line…its clear now. jgrandits…this stuff wont appear on your exam. All the best guys!!