In: Operations Management
PART A: Suppose that a liquor distributor has an average known weekly demand of 10000 units of 1 Liter Makers Mark Bourbon. Each bottle of Makers Mark costs the distributor $25 per bottle. Specifically for the space for this product, it costs the distributor $0.50 per bottle per week to hold in inventory. When the distributor purchases from the manufacturer, they are incurred a $2000 fixed ordering cost. Use this information to answer the following questions
a: What is the optimal order quantity that the distributor should order when they order?
b: How often should the distributor place an order for this quantity?
c: If the distributor follows this ordering policy, what is the total weekly cost of the distributor? Suppose that the distributor makes a mistake, and order 1% more than the optimal policy. What is the percentage difference in cost as a result of ordering 1% more than required?
PART B: Now suppose that the distributor is able to sell each bottle for $35 per bottle. The cost per bottle is the same, namely $25 per bottle. Assume now, however, that demand is random, and that it follows a normal distribution. Use this information to answer the questions below.
a: Assume the average weekly demand is µ = 10000. Find the optimal solution for σ = 500, σ = 1000, σ = 5000, σ = 10000.
b: Let y be the set of optimal solutions, let x be the sigmas from the previous problem. Run a linear regression to find an equation for Q = a + bσ. What are the respective values for a and b?
c: What does this tell us about the optimal ordering policy with respect to the variation in our demand data?
PLEASE SHOW ALL WORK.
ANS
Part A:
Given |
Weekly Demand |
d |
10,000 |
bottles per week |
Cost per order |
S |
$2000 |
Per order |
|
Cost per bottle |
C |
$25 |
Per bottle |
|
Holding cost per unit per week ($) |
H |
$0.50 |
Per bottle per week |
|
Part a. |
EOQ |
Q* |
= √(2 x d x S/H) Q* = √(2 x 10,000 x 2000/0.50)Q* = 8944.27 Or Q* = 8945 |
bottles per order |
ANS a. |
Optimal Order Quantity = 8945 units per order |
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Part b. |
Frequency of ordering |
n |
n = demand/order size n = 10000/8945 n = 1.12 orders per week |
|
Ans b. |
Frequency of order = 1.12 orders per week |
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Part c. |
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Weekly inventory Cost calculation for optimal order Quantity, Q* = 8945 |
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Total weekly inventory Cost = Weekly ordering cost + weekly holding cost |
TC = AHC + AOC TC = [Q/2 x H] + [d/Q x S] |
TC1 = [8945/2 x 0.50] + [10000/8945 x 2000] TC = $2235.89 + $2236.25 TC1 = $4,472.14 |
Per week |
|
Weekly inventory Cost calculation for order Quantity, Q* = 8945 + (0.01*8945) = 9034.45 |
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Total weekly inventory Cost = Weekly ordering cost + weekly holding cost |
TC = AHC + AOC TC = [Q/2 x H] + [d/Q x S] |
TC2 = [9034.45/2 x 0.50] + [10000/9034.45 x 2000] TC = $2236.07 + $2258.61 TC2 = $4,494.38 |
Per week |
|
Percentage difference in cost as a result of ordering 1% more than required optimal quantity |
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Percentage Difference |
% change = (TC2 – TC1) / TC2 |
% change = (4494.38 – 4472.14) / 4472.14 x 100 % change = 0.5% |
Per week |
|
ANS c. |
percentage difference in cost as a result of ordering 1% more than required optimal quantity = 0.5% per week |