A local package delivery service wants to improve the efficiency of its deliveries. As a first step, the management team decides to conduct a study to determine the average length of time from the arrival of a package at the company's mail center until its delivery at a home. Which of the following methods is most likely to produce valid results?Choose 1 answer:(A) The team selects the 1,000 heaviest packages in a one-week, non-holiday period and records how long it takes for each package to reach its destination.(B) The team calls 1,000 residents in their delivery area and asks them whether they have received a package from their service in the past week. They will then record how long it took for those packages to reach their destination.(C) The team selects a random sample of 1,000 packages arriving at the center over a one-week, non-holiday period and records how long it takes for each package to reach its destination.(D) None of the above
Q. A local package delivery service wants to improve the efficiency of its deliveries. As a first step, the management team decides to conduct a study to determine the average length of time from the arrival of a package at the company's mail center until its delivery at a home. Which of the following methods is most likely to produce valid results?Choose 1 answer:(A) The team selects the 1,000 heaviest packages in a one-week, non-holiday period and records how long it takes for each package to reach its destination.(B) The team calls 1,000 residents in their delivery area and asks them whether they have received a package from their service in the past week. They will then record how long it took for those packages to reach their destination.(C) The team selects a random sample of 1,000 packages arriving at the center over a one-week, non-holiday period and records how long it takes for each package to reach its destination.(D) None of the above
Avoid Bias in Selection: The team needs to avoid bias in selecting packages. Choosing the heaviest packages might not represent the average package since weight could affect delivery time.
Rely on Resident Input: Asking residents relies on their memory and honesty, which could introduce errors and bias into the study.
Use Random Sample: A random sample of packages will most likely represent the average package and provide valid results for the study.
Choose Best Method: Option (C) is the best method because it avoids the biases and potential errors of the other options.
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