Statistics
Name BreAnna Gross
Lab Chapters 1 and 2
Describing, Exploring, and Comparing Data
Put answers on this paper, attach work in order if necessary, you may copy graphs
from StatCrunch and paste into this document. Refer to Getting Basic Stats on
Ca
3.6 Use the sketch from Exercise 3.5 and shade in the appropriate areas to answer these
questions. [a] A total of 99.3% of all upper arm lengths are within three standard
deviations of the mean, or between 29.5 centimeters and 42.1 centimeters [h] This is
Chapter 22 - Inference for a Population Proportion
22.1 [a] The population is surgical patients. p is the proportion ot'all surgical
patients who will test positive for Staphylococcus uureus. [b] fa = g = ll. 185, or
18.5%.
22.3 [a] Because up = 030(15ou
Chapter 16 - Condence intervals: The Basics
16.1 [a] The sampling distribution of f has mean p [unknown] and standard deviation
or 125 . . _ . .
= = 6.3931. Accordin to this rule, 95% of all values of it fall 931111 2
"IIJr: :ilTJ [h] 3
standard deviation
Chapter 2 - Describing Distributions with Numbers
2.1 Mean 5: self level is E = w =S_23 per ml. The mean is greater
than most of the observations because of the two outliers [29 Li] and 195.4.
2.3 The mean travel time is E= 31.25 minutes. The median trave
Chapter 1'? - Tests of Signicance: The Basics
111 [a] If ,u = 50. the distribution is sens Hun for n = 125 Phlllppiie sum
approximatelyr Normal with mean manna-sq m.
it! = 5! and standard deviation
UH
i _ i _ as
J: - 225 l. [b] The actual result s
lies ou
Chapter 21 - Comparing Two Means
21.1 This is a matched-pairs design. Each plot is a matched pair.
21.2 This involves two independent samples.
21.3 This involves a single sample.
21.4 This involves two independent samples [because the results for the new
Chapter 1 - Picturing Distributions with Graphs
1.1 [a] The individuals are the car makes and models. [b] For each individual, the
variables recorded are 1-.:"ehicle class [categorical], Transmission type [categorical],
Number of cylinders [usually' treat
Chapter 20 - Inference about a Population Mean
20.1 The standard error ofthe mean is s to"; = 5591111000 = 1.2993 minutes.
2o.s [a] M: 12 - 1 = 11. so 1" = 2.2u1.[hdr=2 1 = 1.50 r = 53.552. [c] df=
1on1 - 1 = 1uou. so r = 1.646.
20.9 [a] df= 5 - 1 = 4 [b]
Chapter 18 - Inference in Practice
1a.: [a] The 95% condence interval is s i zj = 1.92 i 1.96% = 1.92 a duos =
H
1.?99 to 2.011 motorists. [b] The large sample size means that. because of the centlal limit
theorem, the sampling distribution of i is rougth
Chapter 25 - Two Categorical 1variables: The Chi-Square Test
25.5 [a] Expected counts are below observed counts in the table provided. For
cfw_asoxsm
= SURE. We
145.15 [b]
nd that the observed counts are much greater than the expected counts for all
thre
STAT 251G
Online Class
Dr. Rita Eisele
Exam 1: Chapters 1 - 3
Name: _ Date: _
Instructions: Show ALL work or explain your method.
1.
A random sample of 30 states shows the number of low-power FM radio stations for each
state.
Class Limits
1-9
10 - 18
19 -