Statistics

Please see attached for the full details of the problem.

1. (2 pts) The objective of statistics is best described as:

A) To make inferences about a sample based on information we get from a population
B) To make inferences about a population based on information we get from a sample taken from the population
C) To use population mean,  as an estimate of the sample mean,
D) To make inferences about a sample with a high degree of reliability

2. (5 pts) Construct a grouped frequency distribution of the ages that 30 randomly selected smokers started smoking:

25 26 25 17 16 16 14 17 21 16
15 18 17 15 15 19 16 17 23 15
19 17 16 26 16 25 16 17 22 24

3. (2 pts) Three-fourths of the numbers in any data set will be larger than the

A) first quartile B) third quartile C) median D) midrange E) fourth quartile

4. (2 pts) The number that appears most frequently in a data set is the

A) mean B) midrange C) median D) mode E) average

5. (2 pts) Half of the scores in any data set are below the

A) first quartile B) midrange C) third quartile D) median E) fourth quartile

6. (6 pts) Find the mean, median, and mode for the following set of data which shows the number of pages per article in a random sample of magazine articles.

6 7 5 4 7 5 5 7
8 5 3 6 8 9 5

7. (8 pts) Construct a histogram and a frequency polygon for the following frequency distribution

Miles Number of Commuters
Class Frequency
0 - 20 7
21 - 40 3
41 - 60 12
61 - 80 10
81 -100 4

8. (5 pts) State True or False

a) A collection of all the objects to be studied is a population.
b) A subset or part of the population is called a partial population.
c) In a frequency distribution, the class size is always 4.
d) The sum of the percents of the sectors in a pie chart should be 100%.
e) A frequency distribution can be illustrated using a histogram.

9. (6 pts) In a study of 100 married women with children, the subjects were asked the major reason for working outside the home. The study resulted in the following data:

Reason Number of Responses
To support self/family 65
For extra money 20
For something different to do 10
Other 5
----------------------------------------------------------------
Total 100

Construct a pie chart for the data and analyze the results.

10. (2 pts) A county commissioner would like to find out how people in his county feel about a county lottery to support education. How might a cluster sample be selected?

11. (4 pts) The following statistics provide information about the scores on a national History exam.

Mean 540 First Quartile 260
Median 450 Third Quartile 678
Mode 468 90th Percentile 890

a) What score did half of the test takers surpass?
b) What was the most common score?
c) What percentage of the test takers scored 678 or better?
d) If Joe had a score of 890, explain the meaning of his score.