Statistics for the Behavioral Sciences by Frederick J. Gravetter, Larry B. Wallnau ISBN 10: 1305504917 ISBN 13: 9781305504912

664 APPENDIX C | Solutions for Odd-Numbered Problems in the Text
CHAPTER 2
Frequency Distributions
1. X f
7 2
6 3
5 1
4 1
3 4
2 6
1 3
3. a. n = 15
b. ΣX = 41
c. ΣX 2 = 131
5. a. X f b. X f
50–54 2 50–50 2
45–49 2 40–49 4
40–44 2 30–39 4
35–39 1 20–29 8
30–34 3 10–19 6
25–29 5
20–24 3
15–19 5
10–14 1
7. a. 5 points wide and around 7 intervals
b. 2 points wide and around 9 intervals
c. 10 points wide and around 8 intervals
9. A bar graph leaves a space between adjacent bars and
is used with data from nominal or ordinal scales. In
a histogram, adjacent bars touch at the real limits.
Histograms are used to display data from interval or
ratio scales.
11. a. histogram or polygon (ratio scale)
b. bar graph (ordinal scale)
c. bar graph (nominal scale)
d. bar graph (nominal scale)
13. a. n = 17
b. ΣX = 55
c. ΣX 2 = 197
15. a. X f
10 2
9 4
8 5
7 4
6 3
5 2
4 2
3 1
2 1
b. Figure C1
5
4
f
3
2
1
1
2 3 4 5 6 7 8 9 10 11 X
c. 1) The distribution is negatively skewed.
2) The scores are centered around X = 7.
3) The scores are clustered at the high end
of the scale.