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Chapter 4: Q 89. (page 259)

Close shave Which of two brands of electric razor shaves closer? Describe how you would design and carry out an experiment to answer this question using

50adult male volunteers.

Short Answer

Expert verified

Divide volunteers into two groups and make them use one brand to one group and second brand to other group. Compare the results.

Step by step solution

01

Given Information

Here, researcher wants to find out which of the two brands of razor shaves better. There are 50male volunteers to check the effectiveness of razors.

02

Explanation

  • Randomly, divide the volunteers into two groups of 25each.
  • Let first group use one brand and second group use other brand of electric razor.
  • Compare the length of remaining hairs after shaving between individuals of two groups.

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