SOLUTION: Bank customers arrive randomly on weekday afternoons at an average of 3.2 customers every 4 minutes. Required: What is the probability of having more than 7 customers in a 4-minu

Question 1186997: Bank customers arrive randomly on weekday afternoons at an average of 3.2 customers every 4 minutes.
Required:
What is the probability of having more than 7 customers in a 4-minute interval on a weekday afternoon?

Answer by Boreal(15235) (Show Source): You can put this solution on YOUR website!
this is a Poisson distribution with number proportional to time, no upper bound.
the probability for 8 is e^(-3.2)*3.2^8/8=0.0111
for 9 it is e^(-3.2)*3.2^9/9!=0.0039
for 10 it iii 0.0013
for 11 it is 0.0004
on the calculator, use 1-poisssoncdf(3.2, 7) ENTER. The 1- tells the calculator you want everything to the right, not left, and the arguments are the Poisson parameter and the last value you don't want to count, in this case 7.
=0.0168
RELATED QUESTIONS
Customers arrive at a local ice cream stand at an average rate of 16 per hour. (answered by Boreal)

A certain bank is busiest during Friday afternoons. On Friday afternoons, the waiting... (answered by Boreal)

(1) Assume that the time between arrivals of customers at a bank front desk is... (answered by ewatrrr)

d) The arrival rate of customers arriving at a bank counter follows a Poisson... (answered by themasterofcircuits)

Customers arrive randomly at a checkout counter at an average rate of 2 every five... (answered by MathLover1)

customers arrive at a supermarket till at a rate of 2 every 10 minutes. find the expected (answered by jorel1380)

a Bank has 2 tellers. customers arriving at the bank vary between 1 and 6 per minute.... (answered by stanbon)

A local bank has determined that the daily balances of the checking accounts of its... (answered by Boreal)

Customers arrive at the ordering station prior to the drive-through window every 3.6... (answered by 0609077148)