Answer:
a)
b) For this case the new parameter would be:
And we want to calculate the following probability:
And we can use the complement rule for this case:
And for this case we can use the following excel code in order to find the required probability:
"=1-POISSON.DIST(29,30,TRUE)"
And we got:
Step-by-step explanation:
Part a
Let X the random variable that represent the number of cars arriving for gasoline at Shell station. We know that
The probability mass function for the random variable is given by:
And for this case we want this probability:
Using the probability mass function we got:
Part b
For this case the new parameter would be:
And we want to calculate the following probability:
And we can use the complement rule for this case:
And for this case we can use the following excel code in order to find the required probability:
"=1-POISSON.DIST(29,30,TRUE)"
And we got: