Answer:
There is a 0.73% probability that Ben receives a total of 2 phone calls in a week.
Step-by-step explanation:
In a Poisson distribution, the probability that X represents the number of successes of a random variable is given by the following formula:

In which
x is the number of sucesses
is the Euler number
is the mean in the given time interval.
The problem states that:
The number of phone calls that Actuary Ben receives each day has a Poisson distribution with mean 0.1 during each weekday and mean 0.2 each day during the weekend.
To find the mean during the time interval, we have to find the weighed mean of calls he receives per day.
There are 5 weekdays, with a mean of 0.1 calls per day.
The weekend is 2 days long, with a mean of 0.2 calls per day.
So:

If today is Monday, what is the probability that Ben receives a total of 2 phone calls in a week?
This is
. So:


There is a 0.73% probability that Ben receives a total of 2 phone calls in a week.
-4 would be the correct answer to the problem
Unit cost of a ticket = Income from ticket sales / number of tickets sold:
$1250
--------------- = $6.58 per ticket
190 tickets
Again:
$1175
--------------- = $6.71
175 tickets
While ticket prices do change (usually increase) from year to year, it's unusual to see such a situation here.
Don't have any guidelines by which to determine the "fixed cost of a ticket".
If we use the cost of a ticket of 2 years ago ($6.58/ticket), then the income from the sale of 225 tickets this year would be ($6.58/ticket)(225 tickets), or $1480.50.
The last four linesof the poem reveals the solution in the poem as the first reveals the problem