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Educator section



a) R179,97

b) R254,58 (rounded off)

c) R10 665

d) R16 794,75


a) 10,7%

b) 10%

Leaner section


Activity: percentages – discount and increases [lo 1.7, lo 2.7.1]


17.1 Look at the following advertisements

17.2 Did you know?

COST PRICE : The amount that the dealer / trader / merchant pays for an article

MARKED PRICE : This is the price of the article

SELLING PRICE : This is the price after discount

PROFIT : Sale price – cost price

17.3 Work together with a friend through the following problem and solutions:

(i) The price of a tub of margarine is R6,99. If the price is going to rise by 10 %, how much will you have to pay for the margarine in the future?

a) New price is R6,99 + 10% of R6,99= R6,99 + 70 c (rounded off)= R7,69

b) New price is (100 + 10)% of R6,99

= 110% of R6,99

= 110 100 × 699 1 size 12{ {}=` { { size 8{"110"} } over { size 8{"100"} } } times { { size 8{"699"} } over { size 8{1} } } } {}

= R7,69 (rounded off)

Which method do you choose? ..................................................

Why? ……………………………………………………………………………

(ii) Top Teenage T-shirts have a 20 % discount on all T-shirts. If the T-shirt originally cost R189,90, what will you pay for it now?


I only pay 80% (100% - 20% discount)

Thus: 80 100 × 189 , 90 1 size 12{ { { size 8{"80"} } over { size 8{"100"} } } times { { size 8{"189","90"} } over { size 8{1} } } } {}

= R 151, 92


20% of R189,90 = 20 100 × 189 , 90 1 size 12{ { { size 8{"20"} } over { size 8{"100"} } } times { { size 8{"189","90"} } over { size 8{1} } } } {}

The discount is thus R37,98

I pay R189,90 – R37,98 = R151,92

Which method do you choose? ..................................................


17.4 What will you pay for the following items?

17.5.1 Important to remember!

17.5.2 Divide into groups of three. Can you calculate how much % discount was given on the following items?

17.5.3 Explain your method(s) to the rest of the class.


Learning Outcome 1: The learner will be able to recognise, describe and represent numbers and their relationships, and to count, estimate, calculate and check with competence and confidence in solving problems.

Assessment Standard 1.7: We know this when the learner estimates and calculates by selecting and using operations appropriate to solving problems;

Learning Outcome 2: The learner will be able to recognise, describe and represent patterns and relationships, as well as to solve problems using algebraic language and skills.

Assessment Standard 2.7: We know this when the learner determines, analyses and interprets the equivalence of different descriptions of the same relationship or rule presented:

2.7.1 verbally.

Questions & Answers

Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
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
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
what school?
biomolecules are e building blocks of every organics and inorganic materials.
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
sciencedirect big data base
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.
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
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
characteristics of micro business
for teaching engĺish at school how nano technology help us
Do somebody tell me a best nano engineering book for beginners?
s. Reply
there is no specific books for beginners but there is book called principle of nanotechnology
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
fullerene is a bucky ball aka Carbon 60 molecule. It was name by the architect Fuller. He design the geodesic dome. it resembles a soccer ball.
what is the actual application of fullerenes nowadays?
That is a great question Damian. best way to answer that question is to Google it. there are hundreds of applications for buck minister fullerenes, from medical to aerospace. you can also find plenty of research papers that will give you great detail on the potential applications of fullerenes.
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?
carbon nanotubes has various application in fuel cells membrane, current research on cancer drug,and in electronics MEMS and NEMS etc
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
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Source:  OpenStax, Mathematics grade 7. OpenStax CNX. Sep 16, 2009 Download for free at http://cnx.org/content/col11075/1.1
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