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• GETIntPhaseMaths

This module and collection are included inLens: Siyavula: Mathematics (Gr. 4-6)
By: Siyavula

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Course by: Siyavula Uploaders. E-mail the author

To be able to do mental arithmetic

Module by: Siyavula Uploaders. E-mail the author

1.1 20

1.2 28

1.3 25

1.4 24

1.5 6

1.6 76

1.7 9

1.8 7

1.9 48

1.10 11

1.11 30

1.12 8

1.13 9

1.14 12

1.15 9

1.16 108

1.17 45

1.18 81

1.19 7

1.20 12

Content

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

• In Mathematics it is very important that you must be able to think quickly. Let us see how you COPE! Complete the following mental arithmetic test as quickly and accurately as possible.

1.1 5 × 4 = ___________________

1.2 14 + 9 + 5 = ___________________

1.3 32 − 7 + ___________________

1.4 8 × 3 = ___________________

1.5 7 × ___________________ = 42

1.6 Double 38: ___________________

1.7 ___________________ × 8 = 72

1.8 8 × ___________________ = 56

1.9 4 × 12 = ___________________

1.10 ___________________ × 12 = 132

1.11 126 ÷ 6 + 9 = ___________________

1.12 48 ÷ ___________________ = 6

1.13 12 × ___________________ = 108

1.14 ___________________ × 6 = 72

1.15 54 ÷ 6 = ___________________

1.16 Halve 216: ___________________

1.17 ___________________ ÷ 5 = 9

1.18 ___________________ ÷ 9 = 9

1.19 63 ÷ 9 = ___________________

1.20 144 ÷ 12 = ___________________

Complete: I have __________________________ correct.

DID YOU KNOW?

We use the Hindu-Arabic number system!

The ancient Romans developed their counting system more than 2 000 years ago. Some of their figures look like these:

I ; II ; III ; IV ; V

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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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.

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| A lens I own (?)

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?

Any individual member, a community, or a respected organization.

What are tags?

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

| External bookmarks