# OpenStax_CNX

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• GETSenPhaseMaths

This module and collection are included inLens: Siyavula: Mathematics (Gr. 7-9)
By: Siyavula

Module Review Status: In Review
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Inside Collection (Course):

Course by: Siyavula Uploaders. E-mail the author

# Pret met die sakrekenaar

Module by: Siyavula Uploaders. E-mail the author

5. a) 108

b) 9

c) 13

d) 68

e) 14

f) 4

g) 48

h 72

i) 200

j) 18 000

k) 20

l) 9

m) R238

n) R6 080

o) 54

## Inhoud

### AKTIWITEIT: Pret met die sakrekenaar [LU 1.9.2]

#### PRET MET DIE SAKREKENAAR

1. Het jy geweet dat sakrekenaars ook kan “praat”? Sleutel die volgende op jou sakrekenaar in: 0,65 + 0,1234 =

Draai nou jou sakrekenaar onderstebo. Wat lees jy?

___________________________________________________________

In hierdie module gaan ons leer hoe om die sakrekenaar effektief te gebruik om berekeninge maklik te doen.

2. HET JY GEWEET?

5 000 jaar gelede het die Babiloniërs ’n optelmasjien ontwerp wat hulle ’n abakus genoem het. Die Chinese gebruik vandag steeds ’n variasie hiervan. Hulle abakus bestaan uit krale wat jy op ’n telraam op en af moet skuif.

In 1642 het Blaise Pascal van Frankryk ’n optelmasjien ontwerp wat met draaiknoppe gewerk het. Dit was egter te duur om te bou.

’n Britse wiskundige, Charles Babbage, het in 1830 begin werk aan ’n analitiese enjin wat deur stoom aangedryf is. Hy het vir 37 jaar probeer om hierdie enjin , wat verskillende berekeninge kon doen, te bou, maar is oorlede voordat hy dit kon voltooi.

3. KOM ONS HERSIEN

Werk saam met ’n maat en soek die volgende sleutels op jou sakrekenaar:

 AC = wis alles, insluitende die geheue, uit C = maak die vertoonvenster skoon CE / CM = maak die geheue skoon Min / M / M+ ____________________________________ STO = bêre in die geheue / tel op M- = trek van die geheue af RCL / x M ____________________________________ MR / RM = roep die geheue op O m / O m = jy het nie die geheue skoongemaak nie

Het jou sakrekenaar ’n ander sleutel wat jy moet druk om bogenoemde te doen? Skryf dit hieronder neer:

______________________________________________________________

______________________________________________________________

______________________________________________________________

______________________________________________________________

4. ONTHOU JY NOG?

Ons kry ’n gewone sakrekenaar en ’n wetenskaplike sakrekenaar. Laasgenoemde kan meer ingewikkelde berekeninge doen. Vergelyk jou sakrekenaar met dié van jou klasmaats en kyk hoe hul ooreenstem / verskil.

5. Voordat ons verder met die sakrekenaar gaan werk, moet jy eers jou eie breinkrag inspan. Voltooi die volgende hoofrekentoets so vinnig en akkuraat moontlik.

a) 12 × 9 = __________

b) __________ × 7 = 63

c) 48 + __________ = 61

d) __________ - 18 = 50

e) 63 - __________ = 49

f) (12 × 8) + __________ = 100

g) 8 × 3 × 3 = __________

h) __________ ÷ 8 = 9

i) 80 × 40 = __________

j) 300 × 60 __________

k) 500 ÷ 25 = __________

l) one third of 27 = __________

m) R2,38 × 100 = __________

n) R6,08 × 1 000 = __________

o) __________ ÷ 6 = 9

15

Voltooi deur die toepaslike blokkie in te kleur:

 Ek het GOED GEMIDDELD SWAK Gevaar.

## 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 ‘n verskeidenheid tegnieke gebruik om berekeninge te doen, insluitend:

1.9.2: die gebruik van ‘n sakrekenaar.

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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.

##### What is in a lens?

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#### Definition of a lens

##### 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.

##### What is in a lens?

Lens makers point to materials (modules and collections), creating a guide that includes their own comments and descriptive tags about the content.

##### Who can create a lens?

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##### What are tags?

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