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Chapter 4: Q 1.1. (page 233)

Does reducing screen brightness increase battery life in laptop computers? To find out, researchers obtained 30new laptops of the same brand. They chose 15of the computers at random and adjusted their screens to the brightest setting. The other 15laptop screens were left at the default setting鈥攎oderate brightness. Researchers then measured how long each machine鈥檚 battery lasted.

Was this an observational study or an experiment? Justify your answer.

Short Answer

Expert verified

Experimental Study.

Step by step solution

01

Given information

They randomly selected 15 laptops and set their screens to the brightest setting. The default setting for the other 15 laptop screens was moderate brightness.

02

Concept

Observational research looks at people and assesses factors of interest without trying to affect their responses.

Individuals are purposely subjected to a treatment in order to measure their responses in an experiment.

03

Explanation

This is an experimental study in which the evaluation group and the control group are both classes, each with the appropriate variable adjustments to meet the criteria in a controlled setting.

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