Pantry Shopper is a supermarket in suburban Philadelphia, where competition among supermarkets is fierce. Pantry Shopper management feels that because prices are so competitive, shoppers will choose one supermarket over another due to the services offered. For this reason, Pantry Shopper prides itself on its instore bakery; its deli counter, which the store claims offers more varieties of meats, cheeses, and salads than any competitor; and its meat counter, where the store provides custom cuts of meat and poultry. The store has been in business in the same location since 1953. Over the years, the store has had different owners and different managers, each with his or her own ideas on the management and design of the store. The new manager, Beth Smith-Danton, is no exception. Beth felt that by providing shoppers with faster, more efficient service, she might be able to improve the store’s competitive position and market share. To this end, she has already moved check approval from the main desk to the cash register. She has increased the limit on cash back from checks from $20 above the purchase amount to $50 above the purchase amount. She has instituted a delivery service to make shopping more convenient, especially for senior citizens. To this point, however, Beth has not changed the checkout system itself. The last major remodeling of the checkout system occurred in 1982. Since then, the demand at the store has increased and the technology of the cash registers has changed. Beth needs to use her square footage efficiently in redesigning the checkout system. She knows that she has to design the system for peak usage but does not want to overdesign the system-that is, to install too many cash registers and lanes. It’s not that Beth is concerned about the unnecessary expenses, because the registers, scanners, and conveyors represent a fixed cost that would be spread over many shoppers. Wasted space is a far greater concern. Planning for a major redesign, Beth collected data at her store on several consecutive Saturday mornings. She noticed that customers arrived at the checkout at a rate of approximately 100 per hour. Fully 20 percent of the customers had 10 items or less. Those people took about 2 minutes to serve on average, while customers with more than 10 items took about 4 minutes to process. Beth expects service time to improve when universal price code readers are installed in the new design. Help Beth with her design for the system. Assume there are no express lanes and the current average service time with regular lanes is (20% * 2 + 80% * 4 = 3.60 minutes). Solve for 2 scenarios – one with only regular lanes and you must determine how many lanes are needed, and one with separate express lanes for customers with 10 items or less and you must determine how many regular and express lanes are needed. Describe all of the results in making your

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Redesigning Checkout System for Pantry Shopper Supermarket in Suburban Philadelphia

Introduction

In the fiercely competitive suburban Philadelphia market, Pantry Shopper supermarket aims to enhance its market share by providing exceptional services to its customers. Recognizing the significance of efficient service in attracting and retaining shoppers, the store’s new manager, Beth Smith-Danton, is undertaking a major redesign of the checkout system. This essay will explore two scenarios for the redesign, one with only regular lanes and the other with separate express lanes for customers with 10 items or less. The goal is to optimize square footage, minimize wasted space, and improve customer satisfaction while considering peak usage times.

Scenario 1: Regular Lanes Only

To determine the number of regular lanes needed, we first analyze the data collected on consecutive Saturday mornings. The average arrival rate of customers at the checkout is 100 per hour. Among them, 20% of customers have 10 items or less, taking about 2 minutes to serve, while the remaining 80% of customers with more than 10 items take about 4 minutes to process. With this data, the current average service time is calculated as (20% * 2 + 80% * 4 = 3.60 minutes).

To optimize the checkout system and minimize customer wait times, we need to ensure that the system can handle the peak customer demand while avoiding overdesign. Let’s consider a target maximum wait time for customers, say 5 minutes, which is acceptable for most shoppers.

Assuming the checkout system operates at its maximum capacity during peak hours, we can use Little’s Law, which states that the average number of customers in the system (L) is equal to the arrival rate (λ) multiplied by the average time a customer spends in the system (W). Mathematically, L = λ * W.

Given that the arrival rate (λ) is 100 customers per hour and the target maximum wait time (W) is 5 minutes (or 5/60 hours), we can solve for the number of regular lanes (L) needed during peak hours.

L = 100 * 5/60 = 8.33 (rounded up to 9 lanes)

Therefore, to efficiently handle peak demand and keep customer wait times within the acceptable limit, Pantry Shopper would require nine regular lanes.

Scenario 2: Regular and Express Lanes

To further optimize the checkout system and cater to customers with 10 items or less, we can introduce express lanes. These lanes will serve customers with a smaller number of items, reducing their service time and overall wait time.

Given that 20% of customers have 10 items or less, and they take about 2 minutes to serve, we can calculate the arrival rate (λ_e) for express lane customers:

λ_e = 20% of 100 customers per hour = 20 customers per hour

To maintain a target maximum wait time of 5 minutes for express lane customers, we can use Little’s Law again:

L_e = λ_e * W_e

Assuming W_e (average time for express lane customers) is 5 minutes (or 5/60 hours), we can solve for the number of express lanes (L_e) needed during peak hours.

L_e = 20 * 5/60 = 1.67 (rounded up to 2 lanes)

Considering there will be regular lanes and express lanes, we can calculate the number of regular lanes (L_r) required during peak hours:

L_r = L_total – L_e = 9 – 2 = 7 lanes

Conclusion

In conclusion, the optimal checkout system redesign for Pantry Shopper supermarket involves implementing seven regular lanes and two express lanes. This approach ensures efficient service during peak hours, minimizes wasted space, and enhances customer satisfaction. By offering express lanes for customers with 10 items or less, Pantry Shopper will stand out among its competitors, attracting more shoppers and solidifying its competitive position in the suburban Philadelphia market.