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A random sample of 20 people is classified in the following table according to their ages: What is the mean age of this group of people?

Options

  1. A41.0
  2. B41.5
  3. C42.0
  4. D42.5

Correct answer

B. 41.5

Step-by-step solution

Mean age = x_i f_i f_i = 836 20 =41.5

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