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Queueing Theory Calculator

Average Queue Length Formula:

\[ L = \frac{\lambda}{\mu - \lambda} \]

customers/s
customers/s

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1. What is Queueing Theory Calculator?

Definition: This calculator estimates the average queue length in a simple queueing system based on arrival and service rates.

Purpose: It helps operations managers, system designers, and service providers analyze and optimize waiting lines.

2. How Does the Calculator Work?

The calculator uses the formula:

\[ L = \frac{\lambda}{\mu - \lambda} \]

Where:

Explanation: The formula calculates the steady-state average number of customers in the system when arrival and service rates are stable.

3. Importance of Queue Length Calculation

Details: Understanding queue length helps in designing efficient service systems, allocating resources, and improving customer satisfaction.

4. Using the Calculator

Tips: Enter the arrival rate (λ) and service rate (μ) in customers per second. The service rate must be greater than the arrival rate for stable queues.

5. Frequently Asked Questions (FAQ)

Q1: What happens if service rate ≤ arrival rate?
A: The queue becomes unstable and grows infinitely over time. Service rate must exceed arrival rate for stable operations.

Q2: What assumptions does this formula make?
A: It assumes Poisson arrivals, exponential service times, a single server, and infinite queue capacity (M/M/1 model).

Q3: How can I reduce queue length?
A: Either increase service rate (μ) by adding resources or decrease arrival rate (λ) through scheduling or demand management.

Q4: What's a reasonable queue length?
A: This depends on context, but generally L < 1 is excellent, 1-3 is acceptable, and >3 may indicate service problems.

Q5: Can this be used for other queue types?
A: Different formulas exist for multiple servers, limited queue capacity, or different arrival/service distributions.

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