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Grade 9

Number patterns

Graphical representations

Equations statistics

Probability theory

Module 20

Understanding the context and vocabulary of probability

What is gambling all about?


To understand the context and vocabulary of probability

[LO 11.2, 5.1, 5.6]

1 The following very ordinary statements all deal with probability – but they are not all perfectly accurate. With your partner, study them and decide what is left unsaid, or what information you need to be able to evaluate them. Write down the results of your discussion.

For example : “The sun will come up tomorrow morning” really means: “If I go by the fact that the sun has come up every morning of my life, I am very certain that it will happen again tomorrow morning.”

1.1 If I toss a coin, there is a 50:50 chance that it will land tails up.

1.2 Kevin is certain to phone me tonight.

1.3 It is virtually impossible to win the lottery.

1.4 If you have a positive HIV test, then you will die of AIDS.

1.5 You are more likely to die of a spider-bite than of a lightning strike.

1.6 If you are told that every raffle ticket has two numbers, you have a double chance to win.

1.7 If you don’t play the Lotto, you are certain not to win.

1.8 In a room of 24 people, you are likely to find two people with the same birthday.

1.9 There is a 25% chance of rain tomorrow.

1.10 You are as likely to get a three as a four when you throw a die.

  • Check the quality of your answers:

2 Refer to the following scale

  • The likelihood of something happening must lie somewhere along this line of probabilities. Nothing can be less likely than 0%, and nothing can be more likely than 100%. If you throw an ordinary six-sided die, then it is certain (meaning 100% on the above scale) that the number it shows will be either 1, 2, 3, 4, 5 or 6. It is impossible (0%) that it will show a 7. We can’t always be sure exactly where a certain probability lies, but in some cases the probability can be worked out exactly.
  • Write down at which percentage of the scale above each of the following statements falls; afterwards discuss your answers with your partner.

2.1 I will throw a six with an ordinary die.

2.2 If you pick a Smartie with your eyes closed, it will be a red one.

2.3 I will visit a friend next weekend.

2.4 The numbers 1, 2, 3, 4, 5 and 6 are equally likely from throwing a die.

2.5 I will meet the president of South Africa someday.

2.6 I will stay the same height for the next year.

2.7 I will get a cold next winter.

2.8 I will be the president of South Africa someday.

  • How was the quality of my work now?
  • Here is the same scale with other values:

  • These same probabilities are often written as a simplified fraction. Note that the line goes from 0 (impossible) to 1 (certain). We can’t have probabilities that are greater than 1 – nothing can be more likely than absolutely certain! In other words, these probabilities can’t be fractions with a larger numerator than denominator.
  • Let’s look at the die again to make it clear how it works. The dice can show one of six numbers, but the chance that it will be a six is only one out of six chances. Look at it this way: if six friends throw one dice, and each chooses a different number from 1 to 6, then it is certain that one will be right! So, each of them has only 1 of the 6 chances to be right. The fraction (the probability) is 1 6 size 12{ { {1} over {6} } } {} , which lies between 10% and 20% on the scale.

Questions & Answers

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
Do somebody tell me a best nano engineering book for beginners?
s. Reply
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
what is the Synthesis, properties,and applications of carbon nano chemistry
Abhijith Reply
Mostly, they use nano carbon for electronics and for materials to be strengthened.
is Bucky paper clear?
so some one know about replacing silicon atom with phosphorous in semiconductors device?
s. Reply
Yeah, it is a pain to say the least. You basically have to heat the substarte up to around 1000 degrees celcius then pass phosphene gas over top of it, which is explosive and toxic by the way, under very low pressure.
Do you know which machine is used to that process?
how to fabricate graphene ink ?
for screen printed electrodes ?
What is lattice structure?
s. Reply
of graphene you mean?
or in general
in general
Graphene has a hexagonal structure
On having this app for quite a bit time, Haven't realised there's a chat room in it.
what is biological synthesis of nanoparticles
Sanket Reply
what's the easiest and fastest way to the synthesize AgNP?
Damian Reply
types of nano material
abeetha Reply
I start with an easy one. carbon nanotubes woven into a long filament like a string
many many of nanotubes
what is the k.e before it land
what is the function of carbon nanotubes?
I'm interested in nanotube
what is nanomaterials​ and their applications of sensors.
Ramkumar Reply
what is nano technology
Sravani Reply
what is system testing?
preparation of nanomaterial
Victor Reply
Yes, Nanotechnology has a very fast field of applications and their is always something new to do with it...
Himanshu Reply
good afternoon madam
what is system testing
what is the application of nanotechnology?
In this morden time nanotechnology used in many field . 1-Electronics-manufacturad IC ,RAM,MRAM,solar panel etc 2-Helth and Medical-Nanomedicine,Drug Dilivery for cancer treatment etc 3- Atomobile -MEMS, Coating on car etc. and may other field for details you can check at Google
anybody can imagine what will be happen after 100 years from now in nano tech world
after 100 year this will be not nanotechnology maybe this technology name will be change . maybe aftet 100 year . we work on electron lable practically about its properties and behaviour by the different instruments
name doesn't matter , whatever it will be change... I'm taking about effect on circumstances of the microscopic world
how hard could it be to apply nanotechnology against viral infections such HIV or Ebola?
silver nanoparticles could handle the job?
not now but maybe in future only AgNP maybe any other nanomaterials
I'm interested in Nanotube
this technology will not going on for the long time , so I'm thinking about femtotechnology 10^-15
can nanotechnology change the direction of the face of the world
Prasenjit Reply
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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Source:  OpenStax, Mathematics grade 9. OpenStax CNX. Sep 14, 2009 Download for free at http://cnx.org/content/col11056/1.1
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