How Many Observations Should Be Taken to Be 90% Confident

question 22

Multiple Choice

How many observations should be taken to be 90% confident of being within +2% of the actual time a machine is busy if it is believed that the machine is in use 70% of the time?

• A)2,021 observations
• B)1,421 observations
• C)789 observations
• D)365 observations

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Definitions:

Barrier

An obstacle that prevents movement or access, or hinders progress towards a goal.

Effective Communication

The ability to convey information or ideas in a clear, efficient, and understandable manner to the intended audience.

Nonverbal Cues

Communication signals that are not spoken or written but are expressed through body language, facial expressions, gestures, and other physical behaviors.

Ambiguous Words

Words that have more than one interpretation, meaning, or usage, leading to uncertainty or vagueness.