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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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To be able to do mental arithmetic

Module by: Siyavula Uploaders. E-mail the author

MATHEMATICS

Number Concept, Addition and Subtraction

Addition

EDUCATOR SECTION

Memorandum

1.1 830

1.2 14

1.3 12

1.4 99

1.5 27

1.6 12 and a half

1.7 84

1.8 185

1.9 196

1.10 64

1.11 29 and a half

1.12 5

1.13 7

1.14 158

1.15 60

1.16 7

1.17 8

1.18 80

1.19 0

1.20 170

Leaner Section

Content

Activity: To be able to do mental arithmetic [LO 1.9]

  • In this activity it is time again for YOU to rack your brains a bit and to try to enhance your mental arithmetic abilities. See whether you can write down the correct answers of the mental arithmetic test within three minutes!

a) 550 + 280 = ____________

b) 18 + ____________ = 32

c) 28 + ____________ = 40

d) 105 – 6 = ____________

e) 3 × 3 × 3 = ____________

f) Halve van 25 = ____________

g) ____________ ÷ 12 = 7

h) 193 – 8 = ____________

i) 203 – 7 = ____________

j) Halve 128: ____________

k) Halve 59: ____________

l) 20 ÷ ____________ = 4

m) 63 ÷ ____________ = 9

n) Double 79: ____________

o) (6 × 9) + 6 = ____________

p) (7 × 8) + . ____________ = 63

q) (____________ × 5) + 9 = 49

r) 2 × 20 × 2 = ____________

s) ____________ × 12 + 12 = 12

t) Double 85: ____________

Table 1
HOW DID YOU FARE?
MARK THE RELEVANT BOX:
I improved on my previous mental calculation test.  
My marks stayed the same.  
The marks of my previous mental calculation test were better.  

.

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

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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?

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? tag icon

Tags are descriptors added by lens makers to help label content, attaching a vocabulary that is meaningful in the context of the lens.

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