4.1 Measures of dispersion

Instructions:

In this task we will work with the dispersion measures. You will calculate the measures of dispersion for populations and samples, both for ungrouped data and for grouped data. You should present the processes necessary to support the answers to the exercises and round the final results not the intermediate values that appear during the calculations to two decimal places, when necessary.

Question 1

1. Which of the dispersion measures do you like the most? Explain

Question # 2

1. A nutritionist obtains the amounts of sugar (grams) from 10 different cereals, including Cheerios, Corn Flakes, Froot Loops, and seven others. The amounts appear below: 6, 24, 33, 47, 43, 7, 41, 23, 44, 39. Calculate the standard deviation of the amount of sugar in the cereal consumed by the population of all Puerto Ricans who eat cereal (Triola , 2004)

Question # 3

1. The monthly salary of five (5) employees of a pharmaceutical company was as follows: $ 3,667, $ 4,935, $ 3,876, $ 4,700 and $ 3,178. What should the value of the standard deviation be for those data?

Question # 4

1. The waiting times of eight (8) patients to be seen in a medical office, expressed in minutes, were the following: 34, 46, 42, 29, 31, 34, 51, 63. Calculate the following: range, variance and standard deviation.

Question # 5

1. The ages of the 10 best actresses in Hollywood are: 33, 48, 51, 35, 57, 67, 52, 44, 48, 70. Use the 10 ages of the best actresses to calculate the interquartile range.

Question # 6

1. Use the following sample data to calculate the coefficient of variation for each sample; then compare the results.

Weight of students of both sexes at NUC University: 159, 165, 197, 200, 165, 143, 154

Size in inches of babies at birth: 12.2, 15.3, 11.4, 10, 15.8, 13.5, 14.1

Question #7

2)The frequency distribution presented describes the speed at which some young people drove to get to take their classes at the university. These young people were driving on a road with a speed limit of 35 mi / h. Find the variance and standard deviation.

Velocidad Frecuencia

42-45 20

46-49 16

50-53 11

54-57 4

58-61 1

Question # 8

1) The following sample data are presented: 5.1, 3.1, 5.5, 5.1, 8.3, 13.7, 5.3, 4.9, 3.7, 3.8, 9.8. Calculate the following:

a) mean =

b) mode =

c) median =

d) median axis =

e) rank =

f) variance =

g) standard deviation =