Three Messenger Services Deliver To A Small Town In Oregon

Three Messenger Services Deliver To A Small Town In Oregon Service A

Three messenger services deliver to a small town in Oregon. Service A has 60% of all the scheduled deliveries, service B has 30%, and service C has the remaining 10%. Their on-time rates are 80%, 60%, and 40% respectively. Define event O as a service delivers a package on time. Calculate P(A and O). Calculate the probability that a package was delivered on time. If a package was delivered on time, what is the probability that it was service A? If a package was delivered 40 minutes late, what is the probability that it was service B? If a package was delivered 40 minutes late, what is the probability that it was service C?

Paper For Above instruction

Effective and reliable delivery services are crucial for small towns, especially for maintaining communication and commerce. In this context, three messenger services, designated as Service A, Service B, and Service C, operate in a small town in Oregon, each with different shares of total delivery volume and varying on-time performance rates. Analyzing their delivery probabilities and on-time rates provides insights into service reliability and helps customers choose the most dependable courier. This paper aims to compute key probabilities associated with these services, including the likelihood of on-time delivery by Service A, the overall probability of an on-time delivery, and the conditional probabilities that a late delivery is linked to each service. Through the application of probability theory and conditional probability formulas, we will examine the reliability and effectiveness of these delivery services and interpret what these findings imply for consumers and service providers alike.

Let us define the events as follows:

  • A: The package is delivered by Service A
  • B: The package is delivered by Service B
  • C: The package is delivered by Service C
  • O: The package is delivered on time

Given data:

  • P(A) = 0.60, P(B) = 0.30, P(C) = 0.10
  • P(O|A) = 0.80, P(O|B) = 0.60, P(O|C) = 0.40

Calculating P(A and O)

The probability that the package is delivered by Service A and on time is a joint probability, which can be calculated using the multiplication rule of conditional probability:

P(A and O) = P(A) P(O|A) = 0.60 0.80 = 0.48

This indicates that 48% of all deliveries are made on time by Service A.

Calculating the probability that a package was delivered on time (P(O))

The total probability that any package is delivered on time is obtained by summing over all services, considering their respective shares and on-time rates. This employs the law of total probability:

P(O) = P(A) P(O|A) + P(B) P(O|B) + P(C) * P(O|C)

P(O) = (0.60 0.80) + (0.30 0.60) + (0.10 * 0.40) = 0.48 + 0.18 + 0.04 = 0.70

Therefore, there's a 70% chance that any given package is delivered on time.

Conditional probability that a package was delivered by Service A given it was on time

Using Bayes’ theorem:

P(A|O) = P(A and O) / P(O) = 0.48 / 0.70 ≈ 0.686

This means that if a package was delivered on time, there is approximately a 68.6% probability that it was through Service A.

Probability that a package delivered 40 minutes late was by Service B (P(B|Late, 40 min late))

Assuming the probability that a package delivered late (by 40 minutes) is complementary to the on-time rate, the probability it was delivered late by each service is:

  • Service A: P(Late|A) = 1 - 0.80 = 0.20
  • Service B: P(Late|B) = 1 - 0.60 = 0.40
  • Service C: P(Late|C) = 1 - 0.40 = 0.60

The overall probability that a package is delivered late (by 40 minutes) is:

P(Late) = P(A) P(Late|A) + P(B) P(Late|B) + P(C) P(Late|C) = (0.60 0.20) + (0.30 0.40) + (0.10 0.60) = 0.12 + 0.12 + 0.06 = 0.30

Applying Bayes' theorem for Service B:

P(B|Late) = [P(B) * P(Late|B)] / P(Late) = 0.12 / 0.30 = 0.40

Thus, if a package is delivered 40 minutes late, there is a 40% probability it was delivered by Service B.

Probability that a package delivered 40 minutes late was by Service C (P(C|Late, 40 min late))

Similarly, for Service C:

P(C|Late) = [P(C) * P(Late|C)] / P(Late) = 0.06 / 0.30 = 0.20

Therefore, if a package was delayed by 40 minutes, there is a 20% chance it was delivered by Service C.

Conclusion

The analysis clearly shows that Service A dominates the delivery landscape in terms of on-time performance, with about 68.6% of on-time deliveries originating from it. Conversely, Service C, despite its lower volume, has the lowest likelihood of delivering on time and is more associated with late deliveries. Service B sits in the middle, with a consistent profile for late deliveries. These insights can assist both consumers and the service providers in making informed decisions, emphasizing the importance of reliability in service delivery and highlighting areas for potential improvement, particularly for Service C. Improving the on-time rate of Service C could significantly enhance overall delivery reliability and customer satisfaction.

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