The Average Time Before Breakdown of a Machine Is Normally

question 11

Multiple Choice

The average time before breakdown of a machine is normally distributed and has a mean of nine weeks and a standard deviation of 1.5 weeks. If breakdown cost averages $1,500 and preventive maintenance costs $500, what is the optimal preventive maintenance interval?

• A)3.8 weeks
• B)8.4 weeks
• C)9.6 weeks
• D)6.9 weeks
• E)7.2 weeks

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Definitions:

Fast Mapping

A process in language acquisition where children rapidly learn the meaning of a word after just a brief encounter, contributing to vocabulary growth.

Grammatical Morphemes

The smallest units of language that carry meaning and function to indicate tense, number, possession, and other grammatical aspects.

Relations

The way in which two or more concepts, objects, or people are connected; a thing's effect or relevance to another.

Vowels

Vowels are speech sounds produced without any significant constriction or blockage of airflow in the vocal tract, forming the nucleus of syllables in languages.