In: Math
GIVEN:
Orders come to a warehouse facility with an exponentially distributed interarrival time of 20 minutes.
TO FIND:
The probability of having no orders during a given hour period
SOLUTION:
In the given problem, the number of order arrivals per hour follows poisson distribution with probability density function,
where
is the mean number of arrivals per hour (mean arrival rate per
unit time) and we know that the inter-arrival time
follows exponential distribution which is equal to 20 minutes per
order.
Now we will calculate
using inter arrival time and find the probability of having no
orders during a given hour period using probability density
function of poisson distribution.
Inter arrival time
=
Thus mean number of arrivals per hour
is
.
PROBABILITY OF HAVING NO ORDERS DURING GIVEN HOUR PERIOD:
The probability of having no orders (x=0) during a given hour
period with mean arrival rate
is given by,
Thus the probability of having no orders during a given hour period is 0.95.