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Mathematics

Grade 9

Number patterns, graphs, equasions,

Statistics and probability

Module 13

Understand what graphs tell us

Are graphs just pretty pictures?

ACTIVITY 1

To study a number of graphs with the aim of understanding what they can tell one

[LO 1.3, 5.5]

Graph A shows how the number of TV sets owned by every 1 000 people changed between 1985 and 1995 in six different regions in the world. For example, South Asia had 20 TV sets per 1 000 people in 1985, and 55 sets per 1 000 people in 1995.

Graph B shows, on the vertical axis, the number of people in prison in the United States of America in the years shown on the horizontal axis. For e x ample, in 1940 there were 135 000 people in prison.

  • Work in pairs; one person works with graph A, answering question 1 below, and the other with Graph B and question 2. Give the reason or explanation for each of your answers.

1 Study graph A , then write down answers and explanations to these questions:

1.1 Which region had the smallest number of TV sets per 1 000 in 1985?

1.2 Which region had the highest number of TV sets per 1 000 in 1995?

1.3 In which region did the number of TV sets per 1 000 increase the most?

1.4 Is there a region where the number of TV sets per 1 000 has decreased?

1.5 Compare Sub–Saharan Africa with the Arab States and discuss the change in the number of TV sets per 1 000 in these two regions.

1.6 Draw a similar graph showing two other regions: South Africa and the United States of America. Make up the figures.

2 Now study graph B and answer these questions:

2.1 From the graph, try to estimate how many people were in prison in these years:

a) 1930 b) 1950 c) 1995

2.2 In 1980, were there more than or fewer than 200 000 people in jail?

2.3 There is a dip in the graph just after 1940. What do you think the graph is telling us?

2.4 Say roughly how many years it took for the prison population to double from what it was in 1950

2.5 How long did it take the prison population to double from what it was in 1985?

2.6 Would you say that the number of people in jail in the USA keeps increasing? Give reasons.

2.7 From the information in the graph make a prediction about the number of people in USA jails in the future.

3 In Geography, an interesting kind of graph is a section drawing. This shows how the height of the land varies over a straight line between two places. Here is one for the line between Bottelaryberg and Papegaaiberg, two hills near Stellenbosch. All the measurements are in metres. From this we can see (on the left) that Bottelaryberg is about 470 m above sea level, and Papegaaiberg about 255 m above sea level. Walking in a straight line from Bottelaryberg you come to sharp dip, after about 2,5 km, and then, for the next half a kilometre, you go over a little rounded rise.

  • This is a very useful graph for road planners, as it shows the steepness of the terrain.
  • We can clearly see that the descent from the top of Bottelaryberg is very steep, as the line drops sharply over about 750 m. But, if you were on top of Papegaaiberg, and going down in the direction of Bottelaryberg, it would take 1,5 km to drop the same distance, making the route much less steep.

Questions & Answers

where we get a research paper on Nano chemistry....?
Maira Reply
what are the products of Nano chemistry?
Maira Reply
There are lots of products of nano chemistry... Like nano coatings.....carbon fiber.. And lots of others..
learn
Even nanotechnology is pretty much all about chemistry... Its the chemistry on quantum or atomic level
learn
Google
da
no nanotechnology is also a part of physics and maths it requires angle formulas and some pressure regarding concepts
Bhagvanji
Preparation and Applications of Nanomaterial for Drug Delivery
Hafiz Reply
revolt
da
Application of nanotechnology in medicine
what is variations in raman spectra for nanomaterials
Jyoti Reply
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
yes that's correct
Professor
I think
Professor
Nasa has use it in the 60's, copper as water purification in the moon travel.
Alexandre
nanocopper obvius
Alexandre
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
if virus is killing to make ARTIFICIAL DNA OF GRAPHENE FOR KILLED THE VIRUS .THIS IS OUR ASSUMPTION
Anam
analytical skills graphene is prepared to kill any type viruses .
Anam
Any one who tell me about Preparation and application of Nanomaterial for drug Delivery
Hafiz
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
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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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