The Grade Point Averages for 10 Randomly Selected Junior College

question 77

Multiple Choice

The grade point averages for 10 randomly selected junior college students are listed below. Assume the gradepoint averages are normally distributed. Find a 98% confidence interval for the true mean. Round to the nearesthundredth.2.0 3.2 1.8 2.9 0.9 4.0 3.3 2.9 3.6 0.8

• A) (1.55, 3.53)
• B) (0.67, 1.81)
• C) (2.12, 3.14)
• D) (3.11, 4.35)

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Definitions:

Observational Study

A research method where the investigator observes subjects and measures variables of interest without assigning treatments to the subjects.

Observational Study

A study where the researcher observes the outcome without manipulating any variables.

Experiment

An organized procedure to study something under controlled conditions.

Confounded

A situation in experimental design where the effects of two variables cannot be separated, leading to ambiguity in results interpretation.