Chapter 6.5, Problem 10E

Solution

To Find: The error and then correct in the given statement.

The control group is the one who uses their existing hair conditioners.

Given information: A company’s researchers want to check the effects of adding shea butter in the existing hair conditioner of the people. Total $100$ people are selected as volunteers and $50$ are randomly selected in one group who uses existing hair conditioner and the other $50$ are selected in one group who uses shea butter in hair conditioner.

Calculation:

As, the people are randomly chosen and two groups are studied under same conditions except change in one variable which is being studied therefore, this is randomized comparative experiment. The people who are under the normal conditions are called control group. In this case, the control group is those $50$ people who are using their existing hair conditioners.

Hence, the error in the given statement is control group who does not uses either of the conditioner. As, control group uses the existing conditioner.