In: Operations Management
PLEASE SHOW ALL WORK IN EXCEL!!!!!!!
SHOW CALCULATIONS / FORMULAS IN EXCEL!!!!!!!!
Voters arrive at a polling station at an average of 4 per minute (Poisson) where the service rate is 50 per hour (Poisson).
a. What is the average number of voters in the system with 5 voter booths? (10 pts)
b. What is the minimum number of voting booths needed to keep the average time in the system under three minutes? (10 pts)
PLEASE SHOW ALL WORK IN EXCEL!!!!!!!
SHOW CALCULATIONS / FORMULAS IN EXCEL!!!!!!!!
Solution:
Given that
Voters arrive at a polling station at an avg of 4 per minute.
The service rate is 50 per hour.
Determine the given value in the question by using the excel solver in this case:
Using the following excels formula are given below:
Cell |
Formula |
Copy to |
B12 |
=($B$4/$B$5)^A12/FACT(A12) |
B12:B17 |
C16 |
=SUM(B$11:$B15) |
C16:C17 |
D16 |
=+B16/(1-$B$4/(A16*$B$5)) |
D16:D17 |
E16 |
=1/(C16+D16) |
E16:E17 |
F16 |
=$B$4/($B$5*A16) |
F16:F17 |
G16 |
=+E16*B16*F16/(1-F16)^2 |
G16:G17 |
H16 |
=G16+$B$4/$B$5 |
H16:H17 |
I16 |
=G16/$B$4 |
I16:I17 |
J16 |
=I16+1/$B$5 |
J16:J17 |
Arrival rate = 4 per minute = 4*60 per hour = 240 per hour
a) Average number of voters in the system with 5 voter booths (L) = 26.44 (refer cell H16)
b) Target average time in system (W) = 3 minutes = 3/60 hour = 0.05 hour
For s = 6, W = 0.0286, which is less than target W of 0.05
Hence, minimum number of voting booths needed to keep the average time in system under three minutes = 6 voting booths