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Meet bonny and tommy

Educator section


p. 1: When you begin with operations, make the learners aware that the four operations (addition, multiplication, subtraction and division) involve only two different processes:

Two processes Together Separate

This includes concepts like: Add togetherJoinAltogether Take awaySeparateHand out/Divide

Four signs + x _ ¸

differentgroups equalgroups differentgroups equalgroups

Look at schematic representations

+12 + 14 = 35 -26 - 12 = 14

x5 x 3 = 15 ¸30 ¸ 3 = 10

The more the learners see this representation, and hear the explanation, the better they will understand and be able to apply it when solving problems.

The learners must understand the commutative property of addition

(3 + 4 = 7 and 4 + 3 = 7 ) and multiplication ( 2 x 5 = 10 and 5 x 2 = 10 ), but they need not know or use the words “commutative property”.

p. 2: The learners must understand the associative property of subtraction

(9 – 4 = 5 and 9 - 5 = 4 ) and division ( 10 ¸ 2 = 5 and 10 ¸ 5 = 2 ).

p. 3: Learners must first experience with concrete objects how the answers to the subtraction operations can be checked: return what you have taken away and if you have the number you began with, you know your answer is correct. Later this can then be done in writing.

Encourage them to check regularly and later they will do it automatically.

Leaner section


Activity: number sentence [lo 1.9]

  • Bonny has read 3 books and Tommy has read 4 books. Together they have read 7 books.

Number sentence: 3 + 4 = 7

Let’s have Bonny and Tommy change places:

Number sentence: 4 + 3 = 7

  • The numbers on either side of the + sign can change places without the answer changing!
  • Do the same with:
LO 1.9
  • Mom gives Bonny and Tommy 9 apples. Bonny takes 4 apples. There are 5 apples left for Tommy.

Number sentence: 9 - 4 = 5

  • Now let’s give Tommy’s apples first:

Number sentence: 9 - 5 = 4

The numbers on either side of the = sign can change places.

Watch 9 - 4 = 5

carefully! 9 - 5 = 4 Now do the same with:

  • Tommy cannot remember how much money he had in his purse this morning. He knows that he bought fruit for R5 and he now has R3 left. Help him. How much did he have this morning? ____________________________________
LO 1.9
  • Bonny and Tommy want to know if their subtraction number sentences are correct. We can help them to check their sums.

Number sentence: 9 - 4 = 5

Check! Put everything you took away and everything that was left, together again. If you have the same number that you started with, your calculation is correct.

  • Now do the sums and check your answer every time:


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 1.9: We know this when the learner performs mental calculations involving:

1.9.1 addition and subtraction for numbers to at least 50;

1.9.2 multiplication of whole numbers with solutions to at least 50.

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
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 3. OpenStax CNX. Oct 14, 2009 Download for free at http://cnx.org/content/col11128/1.1
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