How to Choose the Most Random Survey

The video tutorial addresses a standardized math test question about selecting a random survey sample. It presents a scenario where a grocery store manager wants to determine the average number of items bought by shoppers in the express checkout lane between 5:00 PM and 7:00 PM. The video evaluates four survey plans, explaining why choices A, B, and C are not random, and concludes that choice D, which involves selecting 8 random 10-minute intervals throughout the week, is the best random sample. The tutorial emphasizes understanding randomness in surveys and concludes with encouragement to continue mastering math.

What is the main objective of the grocery store manager's survey?

• To evaluate the performance of the checkout staff.

• To assess customer satisfaction with the express checkout lane.

• To determine the average number of items bought by shoppers in the express checkout lane.

• To find out the busiest time in the store.

Why is option A not considered a random sample?

• It only includes shoppers on Monday night.

• It selects random shoppers each day.

• It covers the entire week.

• It focuses on a different checkout lane.

What is the main issue with option B?

• It selects random days for the survey.

• It includes all shoppers throughout the week.

• It only considers the first 10 minutes of the time period.

• It focuses on a different time period.

How does option C attempt to introduce randomness?

• By focusing on a different checkout lane.

• By selecting random shoppers each day.

• By choosing a random day of the week.

• By covering the entire time period from 5:00 to 7:00 PM.

What makes option D the best choice for a random sample?

• It selects random shoppers each day.

• It only includes shoppers on Monday night.

• It covers the entire week with random intervals.

• It focuses on a different checkout lane.