Question

A company surveyed all of the employees in their Columbus, Ohio office,

one of their six national offices. Based on the survey they determined that
72% of all employees were satisfied with their job. Which of the following
explains why this is NOT a random sample?
A. They only surveyed people who had been at their job for five years or
more.
B. They did not survey employees in other offices around the country.
C. The survey was conducted electronically.
D. The survey had a time limit.

Answer 1

B. They did not survey employees in other offices around the country

Explanation:

1. A random sample is when you randomly choose options from the whole list. In this case, they make it clear that there are other offices. They didn't give a chance to the rest of the offices to take a survey.

2. Surveying "all" the employees is not what a random sample is. A random sample is supposed to help make it more distributed among the people you survey. Making all of them take it in a cluster is not random.

3. The other choices don't make sense because they don't mention anything about them: nothing about the employees working 5 years, nothing about it being conducted electronically, and nothing about a time limit.