-
Home
- Collaborative statistics:
- Practice exams and quizzes
- Skills practice exams
- Skills practice exam 3: chapters
Questions 1, 2, and 3 refer to the following:
In a study of a sample of 35 Computer Science majors and 40 Business majors, the average number of science fiction books each group read per year was recorded. The Computer Science majors read an average of 11 books with a standard deviation of 4 books. The Business majors read an average of 9 books with a standard deviation of 4.5 books. We are interested in whether the average number of science fiction books read by the Computer Science majors is the same as the number read by the Business majors.
CS = Computer Science majors B = Business majors
Questions 4 and 5 refer to the following:
Suppose that a random survey of 10 teenagers found that the average amount of time they spend on the Internet each day is 3.2 hours with a sample standard deviation of 0.78 hours.
An 87% confidence interval for the average amount of time a teenager spends on the Internet each day would be
-
A
(2.71, 3.68)
-
B
(2.83, 3.57)
-
C
(2.64, 3.76)
-
D
(2.79, 3.61)
Got questions? Get instant answers now!
Which of the following is TRUE about a 99% confidence interval for the true average amount of time that teenagers spend on the Internet each day?
-
I
We are 99% confident that the true average time that teenagers spend on the Internet per day lies within the confidence interval.
-
Ii
The confidence interval contains 99% of the data values collected.
-
Iii
99% of all the confidence intervals constructed this way contain the true average amount of time teenagers spend on the Internet each day.
-
A
I, II, and III
-
B
I and II
-
C
I and III
-
D
I only
Got questions? Get instant answers now!
Questions 7 and 8 refer to the following:
Suppose a random survey of 600 registered voters revealed that only 39% actually voted in the last primary election. We are interested in the population proportion of registered voters who actually voted in the last primary election.
The margin of error (error bound) for a 92% confidence interval for the true proportion of registered voters who actually voted in the last primary election is
-
A
0.0176
-
B
0.3900
-
C
0.3551
-
D
0.0349
Got questions? Get instant answers now!
Suppose you want to redo the survey of registered voters to see how many voted in the last election but this time you survey 1000 registered voters and find 340 voted in the last election. If the confidence level is maintained at 92% what happens to the confidence interval.
-
A
The confidence interval gets wider.
-
B
The confidence interval gets narrower.
-
C
The confidence interval stays the same.
-
D
The confidence interval cannot be calculated.
Got questions? Get instant answers now!
A study of a certain brand of AA batteries yielded a sample mean lifetime of 450 minutes with a sample standard deviation of 92 minutes. A hypothesis test was performed using the following hypotheses:
: m = 480
: m<480
The type I error for this hypothesis test is:
-
A
to conclude that the average battery lifetime is less than 480 minutes when, in reality, it is equal to 480 minutes
-
B
to conclude that the average battery lifetime is equal to 480 minutes when, in reality, it actually is equal to 480 minutes
-
C
to conclude that the average battery lifetime is equal to 480 minutes when, in reality, it is less than 480 minutes
-
D
to conclude that the average battery lifetime is greater than 480 minutes when, in reality, it is equal to 480 minutes
Got questions? Get instant answers now!
Questions & Answers
how does Neisseria cause meningitis
is the branch of biology that deals with the study of microorganisms.
studies of microbes
Louisiaste
when we takee the specimen which lumbar,spin,
How bacteria create energy to survive?
Bacteria doesn't produce energy they are dependent upon their substrate in case of lack of nutrients they are able to make spores which helps them to sustain in harsh environments
_Adnan
But not all bacteria make spores, l mean Eukaryotic cells have Mitochondria which acts as powerhouse for them, since bacteria don't have it, what is the substitution for it?
Muhamad
they make spores
Louisiaste
what is sporadic nd endemic, epidemic
the significance of food webs for disease transmission
Abreham
food webs brings about an infection as an individual depends on number of diseased foods or carriers dully.
Mark
explain assimilatory nitrate reduction
Assimilatory nitrate reduction is a process that occurs in some microorganisms, such as bacteria and archaea, in which nitrate (NO3-) is reduced to nitrite (NO2-), and then further reduced to ammonia (NH3).
Elkana
This process is called assimilatory nitrate reduction because the nitrogen that is produced is incorporated in the cells of microorganisms where it can be used in the synthesis of amino acids and other nitrogen products
Elkana
Examples of thermophilic organisms
Give Examples of thermophilic organisms
Shu
advantages of normal Flora to the host
Prevent foreign microbes to the host
Abubakar
they provide healthier benefits to their hosts
ayesha
They are friends to host only when Host immune system is strong and become enemies when the host immune system is weakened . very bad relationship!
Mark
cell is the smallest unit of life
Fauziya
cell is the smallest unit of life
Akanni
cell is the structural and functional unit of life
Hasan
is the fundamental units of Life
Musa
what are emergency diseases
There are nothing like emergency disease but there are some common medical emergency which can occur simultaneously like Bleeding,heart attack,Breathing difficulties,severe pain heart stock.Hope you will get my point .Have a nice day ❣️
_Adnan
define infection ,prevention and control
Innocent
I think infection prevention and control is the avoidance of all things we do that gives out break of infections and promotion of health practices that promote life
Lubega
Heyy Lubega hussein where are u from?
_Adnan
which site have a normal flora
Many sites of the body have it
Skin
Nasal cavity
Oral cavity
Gastro intestinal tract
Safaa
skin,Oral,Nasal,GIt
Sadik
How can Commensal can Bacteria change into pathogen?
Sadik
How can Commensal Bacteria change into pathogen?
Sadik
what are the advantages of normal Flora to the host
Micheal
what are the ways of control and prevention of nosocomial infection in the hospital
Micheal
part of a tissue or an organ being wounded or bruised.
Wilfred
what term is used to name and classify microorganisms?
Binomial nomenclature
adeolu
Got questions? Join the online conversation and get instant answers!
Source:
OpenStax, Collaborative statistics: supplemental course materials. OpenStax CNX. Oct 01, 2008 Download for free at http://legacy.cnx.org/content/col10586/1.2
Google Play and the Google Play logo are trademarks of Google Inc.