# Question

Many middle schools have initiated a program that provides every student with a free laptop (notebook) computer. Student usage of laptops at a middle school that participates in the initiative was investigated in American Secondary Education (Fall 2009). In a sample of 106 students, the researchers reported the following statistics on how many minutes per day each student used his or her laptop for taking notes:

x = 13.2, s = 19.5

a. Compute the interval, x-bar ±2s.

b. Explain why the distribution of laptop usage for taking notes for these 106 students cannot be symmetric.

c. Given your answer to part b, what percentage of the 106 students have laptop usages that fall within the x-bar ± 2s interval?

x = 13.2, s = 19.5

a. Compute the interval, x-bar ±2s.

b. Explain why the distribution of laptop usage for taking notes for these 106 students cannot be symmetric.

c. Given your answer to part b, what percentage of the 106 students have laptop usages that fall within the x-bar ± 2s interval?

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