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:

Negation

The logical operation that reverses the truth value of a proposition or statement.

Conditional

A statement in logic that asserts if one thing is true, then another will follow.

Truth Values

In logic, the assignment of truth or falsity to propositions, typically modeled as 'true' or 'false'.

Main Connective

The logical operator in a compound statement that determines the statement's overall truth value.