A Recent Survey Was Conducted to Compare the Cost of Solar

question 138

Multiple Choice

A recent survey was conducted to compare the cost of solar energy to the cost of gas or electric energy. Results of the survey revealed that the distribution of the amount of the monthly utility bill of a 3-bedroom house using gas or electric energy had a mean of $90 and a standard deviation of $15. If nothing is known about the shape of the distribution, what percentage of homes will have a monthly utility bill of less than $60?

• A) at least 88.9%
• B) at most 11.1%
• C) at most 25%
• D) at least 75%

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Definitions:

Prototypes

Original or first models of something from which other forms are copied or developed, often used in the context of product design and cognitive psychology.

Heuristic

A mental shortcut that allows people to solve problems and make judgments quickly and efficiently, often using past experiences and common sense.

Decision

The process of making choices by identifying a decision, gathering information, and assessing alternative resolutions.

Polya's Four Steps

A problem-solving approach involving four phases: understanding the problem, devising a plan, carrying out the plan, and looking back at the solution process.