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Chapter 4: Q 3. (page 226)

Sampling stuffed envelopes A large retailer prepares its customers’ monthly credit card bills using an automatic machine that folds the bills, stuffs them

into envelopes, and seals the envelopes for mailing. Are the envelopes completely sealed? Inspectors choose 40 envelopes from 1000 stuffed each hour for visual inspection. Identify the population and the sample.

Short Answer

Expert verified

Yes, the envelopes are sealed.

The population is 1000 envelopes and the sample is 40 envelopes.

Step by step solution

01

Given information

Each hour, inspectors select 40 envelopes from a total of 1000 for visual assessment.

02

Concept

Random sampling uses chance to select a sample.

03

Explanation

The population is defined as the number of envelopes stuffed in an hour. Yes, the envelopes are fully sealed before being mailed. The population refers to the entire group of people for whom data is required. Checking if envelopes are completely sealed is required. A sample is a small portion of a population from which data is gathered. Inspectors select 40 envelopes from a total of 1000 envelopes stuffed in an hour, and the sample is made up of those 40 envelopes.

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