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  • GETIntPhaseMaths display tagshide tags

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

    Module Review Status: In Review
    Collection Review Status: In Review

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To perform mental calculations

Module by: Siyavula Uploaders. E-mail the author

MATHEMATICS

Subtraction

EDUCATOR SECTION

Memorandum

1.1 8 1.9 176

1.2 132 1.10 7

1.3 17 1.11 4

1.4 330 1.12 500

1.5 100 1.13 718

1.6 + 1.14 218 1212 size 12{ { { size 8{1} } over { size 8{2} } } } {}

1.7 100 1.15 10 000

1.8 54

LEANER SECTION

Content

Activity: To perform mental calculations [LO 1.9.1, LO 1.9.2]

1. Until now your mental calculation skills have been of cardinal importance to the activities. This is another opportunity to improve these skills further. Let us see how well you perform in the following mental calculation test. Work as quickly and accurately as possible.

1.1 _____________________ × 9 = 72

1.2 _____________________ ÷ 11 = 12

1.3 119 + _____________________ = 136

1.4 _____________________ – 213 = 117

1.5 30 × _____________________ = 3 000

1.6 967 _____________________ 23 = 990

1.7 86 700 ÷ _____________________ = 867

1.8 (4 × 9) + 18 = _____________________

1.9 (7 + 15) x 8 = _____________________

1.10 (42 ÷ _____________________) + 14 = 20

1.11 (5 × _____________________) – 9 = 11

1.12 Halve × _____________________ = 225

1.13 Double: 359: _____________________

1.14 Halve: 437: _____________________

1.15 104 = _____________________

Complete: I have answered ____________________________ correctly!

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 involving:

1.9.1: addition and subtraction;

1.9.2: multiplication of whole numbers to at least 12 x 12.

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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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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.

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What are tags? tag icon

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| External bookmarks