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Vigorous exercise helps people live several years longer (on average). Whether mild activities like slow walking extend life is not clear. Suppose that the added life expectancy from regular slow walking is just 2 months. A statistical test is more likely to find a significant increase in mean life expectancy if:_______.
A. respondents tell the truth about exercising.
B. the size of the sample doesn't have any effect on the significance of the test.
C. 95% confidence is high enough.
D. it is based on a very large random sample.
E. it is based on a very small random sample.
Hint:Think about the importance of the sample size.

Respuesta :

Using the concept of margin of error, it is found that higher samples lead to more precise results, hence the correct option is:

D. it is based on a very large random sample.

What is the margin of error of a confidence interval?

The margin of error of a confidence interval is given by:

[tex]M = z\frac{s}{\sqrt{n}}[/tex]

In which:

  • z is the critical valuer related to the confidence value, the higher the confidence level the higher z.
  • s is the standard deviation.
  • n is the sample size.

In this problem the increase in life expectancy regarding regular slow walking should be considerably greater than 2 months, which means that the a larger sample is needed to give a more precise result, hence option D is correct.

You can learn more about margin of error at https://brainly.com/question/25821952

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