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Seeing that 3x and ÷ have just been done, it is easy to introduce thirds now. Give the learners loose paper shapes and allow them to fold and measure on their own, so that they can discover how it can be done. Some of the learners will know how to find sixths without any help. (Only enrichment)

The idea with the recipe is to make the learners understand that certain standard units and containers must be used, otherwise there is no chance of success with a recipe.

Let the learners mention more examples of the use of standard units in practice, e.g. petrol, milk, mixing medicines, prescriptions for administering medication, etc.

It is essential that all the different standard measuring containers and scales, as well as sand, water and objects used in measuring volume and mass , should be available in the classroom. Learners should be able to experiment every day with measuring and weighing, using standard units: litres and millilitres and grams and milligrams .

A bathroom scale is required to determine the mass of the learners.

Different methods are used for the multiplication and division calculations, but should you prefer another method and you find that the learners understand it better, it is their right to use the preferred method.

It is essential that many similar examples of the relevant number sentences be done orally before the learners are expected to complete this worksheet.

The regrouping of a hundred when adding or subtracting is now formally taught. Sufficient concrete work must be done beforehand. More advanced work where a ten and a hundred are regrouped simultaneously, should not be done at the same time. It will depend on the abilities of the group whether it should be done immediately hereafter or at a much later stage.

Whether the learners will be allowed to make use of carried numbers, remains the decision of the educator. e.g.

Learners will need a blank sheet of paper in order to calculate the shortest route. Some learners may find it difficult and may want to give up, but with a little help they should be able to do it.

A discussion on what they will see as they approach the farmstead by road is necessary before the learners will be able to draw it.

Leaner section

Content

Activity: to measure [lo 1.1, lo 1.4, lo 1.11, lo 4.5]

In order to measure accurately , we have to make use of standard units . Shorter lengths are measured in centimetres and millimetres . We can use a ruler to do this. 10mm = 1 cm

Longer lengths are measured in metres and for this we can use a metre stick, a tape measure or a trundle wheel. 100cm = 1 m

. metre 1 2 3 4 5 6 7 8 9
centimetre 100
  • Use your ruler and measure the lengths:
  • Use your ruler and draw a line 14cm long . Now halve it.
  • Draw a line 12cm long and divide it into 4 quarters .
  • Use the metre stick to measure two objects in the classroom that are longer than your ruler but shorter than the metre stick. Estimate first .
Object Estimated Measured Too much or too little
  • Use the tape measure to measure the height of two of your friends. Estimate first .
Object Estimated Measured Too much or too little
  • Use the trundle wheel to measure the length of the stoep or the corridor.
  • Measure it . It is __________________________________ long.
  • I was wrong by _____________________________________________
  • Tommy is going to help Grandpa to make a new camp for Granny’s chickens. The new camp will be rectangular - 50m long and 30m wide.
  • Measure the length of the 4 sides of this rectangle.

AD = _____________________________________________

AB = _____________________________________________

BC = _____________________________________________

CD = _____________________________________________

We discover: AD = BC and AB = CD

The two opposite sides of a rectangle are of the same length .

Thus : 2 times the length plus 2 times the width (breadth) is equal to the perimeter of the rectangle . ( 2 x l ) + ( 2 x b ) = perimeter

This is how we write it: 2 l + 2 b = perimeter

  • 2 times the lengths is _________ cm and 2 times the width is __________ cm.
  • The perimeter of the rectangle is _________________________________ cm.

Now Bonny and Tommy know how to calculate what length of wire netting is needed to make the camp. They only have to calculate the perimeter of the camp.

  • 2 times the length is___________ m and 2 times the width is _________ m.
  • 2 l + 2 b = perimeter

_____ + _____ =

  • The perimeter of the camp is ____________________________________ m.
  • The camp will have a wooden gate that is 1m in width. Thus Grandpa has to buy only ________________________ m wire netting.
  • The rectangle has been divided into three equal parts . Colour in 1 of the 3 parts.

  • Show how you will solve the problems. You may draw.

Granny baked 24 cookies. Bonny and Tommy ate ¼ of them.

How many cookies are left?

There are ________________________________________________

  • Bonny and Tommy each got R12 from Grandpa. Bonny spent ½
    of her money and Tommy spent ⅓ of his. Who spent more?

__________________________________________ spent more.

  • Tommy is 1m 37cm tall and Freddie is 1m 43cm. What is the difference between their lengths?

The difference is _______________________________________________________

  • Grandpa buys a rope that is 16m long. How many 2m-pieces can he cut from it?

He can cut ____________________________________________________________

Assessment

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 1.4: We know this when the learner orders, describes and compares numbers;

Assessment Standard 1.11: We know this when the learner explains own solutions to problems;

Learning Outcome 4: The learner will be able to use appropriate measuring units, instruments and formulae in a variety of contexts.

Assessment 4.5: We know this when the learner estimates, measures, compares and orders three-dimensional objects using non-standard and standard measures.

Questions & Answers

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
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
NANO
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
s.
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.
Tarell
what is the actual application of fullerenes nowadays?
Damian
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.
Tarell
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.
Virgil
is Bucky paper clear?
CYNTHIA
carbon nanotubes has various application in fuel cells membrane, current research on cancer drug,and in electronics MEMS and NEMS etc
NANO
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.
Harper
Do you know which machine is used to that process?
s.
how to fabricate graphene ink ?
SUYASH Reply
for screen printed electrodes ?
SUYASH
What is lattice structure?
s. Reply
of graphene you mean?
Ebrahim
or in general
Ebrahim
in general
s.
Graphene has a hexagonal structure
tahir
On having this app for quite a bit time, Haven't realised there's a chat room in it.
Cied
Got questions? Join the online conversation and get instant answers!
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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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