Suppose a Research Firm Conducted a Survey to Determine the Average

question 8

Multiple Choice

Suppose a research firm conducted a survey to determine the average amount of money steady smokers spend on cigarettes during a week. A sample of 100 steady smokers revealed that the sample mean is $80 and the sample standard deviation is $20. What is the probability that a sample of 100 steady smokers spend between $76 and $84?

• A) 0.4772
• B) 0.0228
• C) 0.9544
• D) 0.3400
• E) 0.9999

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Definitions:

Significance Level

A threshold for determining whether a statistical result obtained is not attributed to chance, commonly set at values like 0.05, indicating a 5% risk of error.

Statistically Significant

A measure used to determine if the results of a study are unlikely to have occurred by random chance alone, often through a p-value.

Confidence Interval

A collection of values, drawn from sample data, that is presumed to capture the value of a not yet known population characteristic.

National Average

The average of a specific set of measurements or data points across the entire nation.