SOLUTIONS TO EXERCISES
About these solutions
The solutions that follow were prepared by Jackie Miller, although some of these have their
roots in solutions prepared by Bill Notz, David Moore, and Darryl Nester, for the previous
editions, and modified (or
6.2 Part II Solutions
Chapter 10 Solutions
10.1. State is categorical. To show the distribution you would use a bar graph. We cannot use a
pie chart because the data are seven separate quantities, not the parts of some whole.
10.2. There is a sharp increa
Solutions Part I: Chapters 1 to 9
307
Chapter 4 Solutions
4.1. This question is clearly slanted toward a positive (yes) response.
4.2. Label faculty 0, 1, 2, 3, 4. Label students 0, 1, 2, 3, 4, 5, 6, 7, 8, 9. Starting at line 111 in
Table A, we choose as
Solutions Part I: Chapters 1 to 9
303
Chapter 3 Solutions
3.1. The margin of error for 95% confidence will be about
(that is, 3.2%)
3.2. The margin of error for 95% confidence will be about
(that is, 1.6%)
It is smaller than for a sample of 1007. (In fact
Solutions Part II: Chapters 10 to 16
377
Chapter 16 Solutions
16.1.
.
16.2.
The real income increased by only
.
16.3. Index number (1987) = 0.95/1.23 100 = 77.2; index number (1997) = 100; index number
(2007) = 2.80/1.23 100 = 227.6.
16.4. (a) Tuition ros
Solutions Part I: Chapters 1 to 9
325
Chapter 8 Solutions
8.1. The number of drivers is usually much larger between 5 and 6 PM (rush hour) than between
1 and 2 PM. Thus, we would expect the number of accidents to be greater between 5 and 6 PM
than between
Solutions Part II: Chapters 10 to 16
359
Chapter 13 Solutions
13.1. The central 95% of any normal distribution lies within two standard deviations of the mean.
Two standard deviations is 5 inches here, so the middle 95% of young mens heights is between
65
Solutions Part I: Chapters 1 to 9
317
Chapter 6 Solutions
6.1. There are two explanatory variables. These are baking temperature (300, 320, and 340F)
and baking time (1 hour and 1.25 hours). The responses are the scores of the panel of tasters for
texture
352
Solutions to Exercises
Chapter 12 Solutions
12.1. There are 22 observations, and the median lies halfway between the middle pair (the 11th
and 12th largest). The middle two values are 35 and 41, so the median is M = (35 + 41)/2 = 76/2
= 38. There are
Solutions Part II: Chapters 10 to 16
369
Chapter 15 Solutions
15.1. The predicted humerus length for a fossil with a femur 70 cm long is
15.2. The proportion of the variation in hot dog prices that is explained by the least-squares
regression of hot dog p
Solutions Part II: Chapters 10 to 16
363
Chapter 14 Solutions
14.1. The researchers are seeking to predict IQ from brain size. Thus, there is an explanatory
variable (brain size). The response variable is IQ. The following is a scatterplot of the data:
14
Cliente
Cant.
Producto
A
A
A
FECHA
CLIENTE
Maria Beatriz Viana
Beatriz Lucia Fernandez de Soto
Aida paulina Fernandez de Soto
Olga Maria Fernandez de Soto
Maria Clara Montalvo
Claudia Orozco
Maria Clara Chamat
Maria Mercedes Chamat
Cristina Astudillo
Isab
Chapter 17 Solutions
17.1. All of the outcomes are equally probable if the coin is fair because heads and tails are
equally likely. Thus, all sequences of 10 particular outcomes are equally likely.
17.2. A correct statement might be, If you tossed a coin
392
Solutions to Exercises
Chapter 18 Solutions
18.1. Let a pair of numbers represent the number of spots of the up-faces of the first and second
die, respectively. The probability of rolling a 7 is:
The probability of rolling an 11 is:
By Rule D, the pro
Solutions Part I: Chapters 1 to 9
329
Chapter 9 Solutions
9.1. According to Census Bureau estimates, the population in the United States as of July 1,
1976, was 218,035,164. If there were 80 million Baptists and even more Roman Catholics, then
Baptists an
Solutions Part II: Chapters 10 to 16
345
Chapter 11 Solutions
11.1. Step 1: Divide the range of the data into classes of equal width. The data in the table
range from 39.9 to 46.7, so we choose as our classes
39.0 percentage 15 to 44 < 40.0
40.0 percentag
324
Solutions to Exercises
Chapter 7 Solutions
Many of the questions in this chapter are matters of opinion, and may be better used for class
discussion rather than as assigned homework. A few comments are included here.
7.1. This patients underlying dise
Solutions Part I: Chapters 1 to 9
299
Chapter 2 Solutions
For these exercises, remind students that the population is the group about which information is
desired, which is not necessarily the group represented by the sample.
2.1. This is not a simple ran