1. With the following data, determine:

The values correspond to the age of a group of physics students:

18 25 19 21 20 30 25 28 22 26

a. rank

b. Interquartile range

C. Interfractile interval between the first and second third.

2. The following is a sample of people visiting an office in one day.

People

20

15

15

10

a. Calculate the standard deviation for this sample.

b. If the distribution is biased, determine the interval between plus or minus 2 standard deviations

C. How many data in the sample are estimated to fall in the interval calculated in the previous question?

3. The following table corresponds to the duration of a phone call in minutes.

classes

(minutes) frequency

2-4 2

5-7 6

8-10 7

Calculate the standard deviation of the call.

4. A company is considering using one of two training methods.Two groups of employees trained for the same task. Group 1 trained-under Program A and group 2 under Program B. The average time required to train the employee is 32.11 hours with a variance of 68.09 for the Program A. The average time of 19.75 hours and the variance of 71.14 hours for Program B. Which training program has the least relative dispersion in its execution? Why?