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For each problem:

  • In words, define the Random Variable X size 12{X} {} .
  • List the values that X may take on.
  • Give the distribution of X . X ~
Then, answer the questions specific to each individual problem.

Six different colored dice are rolled. Of interest is the number of dice that show a “1.”

  • On average, how many dice would you expect to show a “1”?
  • Find the probability that all six dice show a “1.”
  • Is it more likely that 3 or that 4 dice will show a “1”? Use numbers to justify your answer numerically.
  • X size 12{X} {} = the number of dice that show a 1
  • 0,1,2,3,4,5,6
  • X ~ B ( 6 , 1 6 )
  • 1
  • 0.00002
  • 3 dice

More than 96 percent of the very largest colleges and universities (more than 15,000 total enrollments) have some online offerings. Suppose you randomly pick 13 such institutions. We are interested in the number that offer distance learning courses. (Source: http://en.wikipedia.org/wiki/Distance_education)

  • On average, how many schools would you expect to offer such courses?
  • Find the probability that at most 6 offer such courses.
  • Is it more likely that 0 or that 13 will offer such courses? Use numbers to justify your answer numerically and answer in a complete sentence.

A school newspaper reporter decides to randomly survey 12 students to see if they will attend Tet (Vietnamese New Year) festivities this year. Based on past years, she knows that 18% of students attend Tet festivities. We are interested in the number of students who will attend the festivities.

  • How many of the 12 students do we expect to attend the festivities?
  • Find the probability that at most 4 students will attend.
  • Find the probability that more than 2 students will attend.
  • X size 12{X} {} = the number of students that will attend Tet.
  • 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12
  • X ~ B(12,0.18)
  • 2.16
  • 0.9511
  • 0.3702

Suppose that about 85% of graduating students attend their graduation. A group of 22 graduating students is randomly chosen.

  • How many are expected to attend their graduation?
  • Find the probability that 17 or 18 attend.
  • Based on numerical values, would you be surprised if all 22 attended graduation? Justify your answer numerically.

At The Fencing Center, 60% of the fencers use the foil as their main weapon. We randomly survey 25 fencers at The Fencing Center. We are interested in the numbers that do not use the foil as their main weapon.

  • How many are expected to not use the foil as their main weapon?
  • Find the probability that six do not use the foil as their main weapon.
  • Based on numerical values, would you be surprised if all 25 did not use foil as their main weapon? Justify your answer numerically.
  • X size 12{X} {} = the number of fencers that do not use foil as their main weapon
  • 0, 1, 2, 3,... 25
  • X ~ B(25,0.40)
  • 10
  • 0.0442
  • Yes

Approximately 8% of students at a local high school participate in after-school sports all four years of high school. A group of 60 seniors is randomly chosen. Of interest is the number that participated in after-school sports all four years of high school.

  • How many seniors are expected to have participated in after-school sports all four years of high school?
  • Based on numerical values, would you be surprised if none of the seniors participated in after-school sports all four years of high school? Justify your answer numerically.
  • Based upon numerical values, is it more likely that 4 or that 5 of the seniors participated in after-school sports all four years of high school? Justify your answer numerically.

Questions & Answers

I only see partial conversation and what's the question here!
Crow Reply
what about nanotechnology for water purification
RAW Reply
please someone correct me if I'm wrong but I think one can use nanoparticles, specially silver nanoparticles for water treatment.
Damian
what is the stm
Brian Reply
is there industrial application of fullrenes. What is the method to prepare fullrene on large scale.?
Rafiq
industrial application...? mmm I think on the medical side as drug carrier, but you should go deeper on your research, I may be wrong
Damian
How we are making nano material?
LITNING Reply
what is a peer
LITNING Reply
What is meant by 'nano scale'?
LITNING Reply
What is STMs full form?
LITNING
scanning tunneling microscope
Sahil
how nano science is used for hydrophobicity
Santosh
Do u think that Graphene and Fullrene fiber can be used to make Air Plane body structure the lightest and strongest. Rafiq
Rafiq
what is differents between GO and RGO?
Mahi
what is simplest way to understand the applications of nano robots used to detect the cancer affected cell of human body.? How this robot is carried to required site of body cell.? what will be the carrier material and how can be detected that correct delivery of drug is done Rafiq
Rafiq
what is Nano technology ?
Bob Reply
write examples of Nano molecule?
Bob
The nanotechnology is as new science, to scale nanometric
brayan
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Damian
Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
Renato
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
why we need to study biomolecules, molecular biology in nanotechnology?
Adin Reply
?
Kyle
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
Adin
why?
Adin
what school?
Kyle
biomolecules are e building blocks of every organics and inorganic materials.
Joe
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
research.net
kanaga
sciencedirect big data base
Ernesto
Introduction about quantum dots in nanotechnology
Praveena Reply
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
Bharti
do you think it's worthwhile in the long term to study the effects and possibilities of nanotechnology on viral treatment?
Damian Reply
absolutely yes
Daniel
how to know photocatalytic properties of tio2 nanoparticles...what to do now
Akash Reply
it is a goid question and i want to know the answer as well
Maciej
characteristics of micro business
Abigail
for teaching engĺish at school how nano technology help us
Anassong
How can I make nanorobot?
Lily
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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Source:  OpenStax, Collaborative statistics (custom lecture version modified by t. short). OpenStax CNX. Jul 15, 2013 Download for free at http://cnx.org/content/col11543/1.1
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