A personal trainer thinks her clients get better workouts and are stronger if they listen to music while working out. Over the next week, she divides her 20 clients into two groups of 10. For the first group, she plays music and sees if they can lift a barbell weighing 50 lbs. For the second group, she repeats the test but does not play any music. All 10 members of the music group could lift the barbell, but only 7 members of the no music group could lift the barbell. She concludes that her hypothesis was correct and decides to always play music for her clients. Which group was the control group?

The correct answer is: the group of 10 people that lifted the barbell with music is the control group.

Explanation:

The personal trainer made an experiment to test her hypothesis. When experiments are being made, is common to have a control group and an experimental group.

The control group is the one that is subjected to the usual conditions, the group that shows what normally happens. The experimental group is the opposite, this group is observed while it goes through an unusual condition that may impact how they perform in the task observed.

The personal trainer thinks that playing music for her clients is of benefit to them, so we can assume that she always plays music during the workouts, which means that the control group is the one that is listening to music while lifting a barbell. The group that worked out without music is the experimental group because they were the ones that performed that activity with a change in their normal environment.

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