The Mean Length of Time, Per Week, That Students at a Certain

question 97

Multiple Choice

The mean length of time, per week, that students at a certain school spend on their homework is 24.3 hours, with a standard deviation of 1.4 hours. Assuming the distribution of study times is Normal, what percent of students spend more than 25.238 hours per week on homework? Use the fact that the middle 50% of the data falls within 0.67 standard deviations from the mean.

• A) 16.5%
• B) 5%
• C) 12.5%
• D) 25%

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Definitions:

Population

The entire group of individuals or items that share one or more characteristics, from which samples may be drawn for statistical analysis.

Sample Value

A single observation or measurement taken from a larger set of data, known as a sample.

Significant Difference

A statistical assessment that shows that the observed results in a study were unlikely to have occurred by chance.

Standard Error

The standard deviation of the sampling distribution of a statistic, typically used to measure the accuracy of sample mean estimates.