Calculate the mean and the standard deviation of the age of individuals that purchased skateboarding shoes. Use 10 as the midpoint of the first class. (Do not round intermediate calculations. Round your answers to 2 decimal places.)

Respuesta :

Answer:

Mean = 19.84

Standard deviation = 11.12

Step-by-step explanation:

Note: This question is not complete. The complete question is therefore provided before answering the question. See the attached pdf file for the complete question.

The explanation of the answer is now given as follows:

Note: See the attached excel file for the calculation of the total of fx and total of f*x^2.

N = Number of individuals sampled = 200

From the attached excel file, we have:

Total of fx = 3,967

Total of f*x^2 = 103,425.50

Therefore, we have:

Mean = Total of fx / N = 3,967 / 200 = 19.84

Variance = (Total of f*x^2 / N) - Mean^2 = (103,425.50 / 200) - 19.84^2 = 517.13 - 393.43 = 123.70

Standard deviation = Variance^0.5 = 123.70^0.5 = 11.12

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