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  • GETIntPhaseMaths display tagshide tags

    This module is included inLens: Siyavula: Mathematics (Gr. 4-6)
    By: Siyavula

    Review Status: In Review

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Om hoofreken te kan doen

Module by: Siyavula Uploaders. E-mail the author

WISKUNDE

Getalbegrip, Optelling en Aftrekking

Aftrekking

OPVOEDERS AFDELING

Memorandum

2. Aftrekking

3.1 8

3.2 28

3.3 47

3.4 40

3.5 340

3.6 3 580

3.7 18 200

3.8 18 050

3.9 10 250

3.10 8 250

3.11 18

3.12 14

3.13 8

3.14 12

3.15 45

3.16 450

3.17 350

25 000

3.19 1 500

3.20 250

LEERDERS AFDELING

Inhoud

AKTIWITEIT: Om hoofreken te kan doen [LU 1.9]

1. Dit is dikwels vir ons nodig om vinnig te kan optel of aftrek. Ons moet altyd probeer om “kortpaaie” te kry vir die hoofreken. Kan jy bv. dink aan ‘n manier om vinnig 9 van ‘n getal af te trek? (Kyk gerus wie in jou klas die effektiefste metode hiervoor het)

2. Is jy nou reg vir aksie?? Trek 9 af van elk van die volgende getalle. Skryf die letter regoor die korrekte antwoord neer en vind so uit waarmee ons in hierdie leereenheid besig gaan wees!

Tabel 1
18 31 22 47 25 34 24 47 43 26 14
                     

Figuur 1
Figuur 1 (graphics1.png)

  • Skryf jou antwoord hier neer:

_____________________________________________________________________

_____________________________________________________________________

_____________________________________________________________________

_____________________________________________________________________

  • Onthou jy nog?

In die som 468 – 231 = 237 noem ons468 die aftrektal231 die aftrekker237 die verskil

Tabel 2
Dus: 468 - 231 = 237  
       
  aftrektal aftrekker verskil
  • Onthou jy ook nog?

Die INVERSE (omgekeerde bewerking) van aftrekking is OPTELLING.

As jy dus ’n aftreksom wil toets, moet jy optel.

3. Kom ons oefen nou eers jou hoofrekenvaardighede. Trek die volgende af so vinnig en akkuraat moontlik. As jy jou plekwaardes ken (kyk weer na Leereenheid 1) sal dit sommer kinderspeletjies vir jou wees.

2.1 17 – 9 = _________________

2.2 37 – 9 = _________________

2.3 97 – 50 = _________________

2.4 97 – 57 = _________________

2.5 360 – 20 = _________________

2.6 3 600 – 20 = _________________

2.7 18 250 – 50 = _________________

2.8 18 250 – 200 = _________________

2.9 18 250 – 8 000 = _________________

2.10 18 250 – 10 000 = _________________

2.11 _________________ – 9 = 9

2.12 _________________ – 8 = 6

2.13 21 – _________________ = 13

2.14 42 – _________________ = 30

2.15 90 – _________________ = 45

2.16 900 – _________________ = 450

2.17 900 – _________________ = 550

2.18 _________________ – 6 000 = 19 000

2.19 21 500 – _________________ = 20 000

2.20 25 750 – _________________ = 25 500

  • Voltooi die volgende met ’n regmerkie:
Tabel 3
    GLAD NIE   NET ‘N BIETJIE   BAIE   VREES-LIK BAIE
Ek sukkel om vinnig en akkuraat af te trek                
                 
Ek sukkel om vinnig af te trek                
                 
Ek sukkel om korrek af te trek                

Assessering

Leeruitkomste 1:Die leerder is in staat om getalle en die verwantskappe daarvan te herken, te beskryf en voor te stel, en om tydens probleemoplossing bevoeg en met selfvertroue te tel, te skat, te bereken en te kontroleer.

Assesseringstandaard 1.9: Dit is duidelik wanneer die leerder hoofberekeninge uitvoer wat die volgende behels:

1.9.1 optelling en aftrekking;

1.9.2 vermenigvuldiging van heelgetalle tot minstens 10 × 10.

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Lenses

A lens is a custom view of the content in the repository. You can think of it as a fancy kind of list that will let you see content through the eyes of organizations and people you trust.

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