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An Introduction to Statistics

Odd Solution for Statistics Lesson 6

  1. Find the mean, and standard deviation for the data set below.
    ProfessionSalaryfrequency
    Teacher36,0001,000,000
    notebook assembler360,000100,000
    Netscape® programmer3,600,000100
    Windows® programmer36,000,00010
    Bill Gates360,000,0001

    mean = 66400 (66429.6); s = 373000 (373243.6)

  3. Apply the symmetry of IQ distribution and the empirical rule (68-95-99.7) to find the proportion of a population with an IQ between 85 and 130.
    68/2 + 95/2 = 34 + 47.5 = 81.5%

  5. The Unibomber (Theodore Kaczynski) has been often cited with an IQ of 170. Calculute how many standard deviations above the mean this corresponds to.
    Z = (170 - 100)/15 = 4.67 standard deviation from the mean

  7. What percent of the inauguration data is within two standard deviations of the mean?
    39/42 = 93%

  9. Add five years (L1+5=>L2) to your presidential inauguration data and recompute the mean and standard deviation. How did they each change?

     

  11. Add 5 years then increase your original presidential inauguration data by 10% ((L1+5)×1.1=>L2) and recompute the mean and standard deviation. How did they each change?

     

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