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• GETIntPhaseMaths

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

Review Status: In Review

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# To perform mental calculations

Module by: Siyavula Uploaders. E-mail the author

## Memorandum

• 203; 190; 173; 208; 236; 222; 253; 471; 570; 459; 423; 472; 430; 343; 453; 357; 315

1 000 000

## LEANER SECTION

### COMPETITION TIME!

• Compete with a friend to see who can complete this arrow diagram CORRECTLY first! You may not use a pocket calculator.

#### THE REMARKABLE MILLION!

10 x 10 = 100

100 x 10 = 1 000

1 000 x 10 = 10 000

10 000 x 10 = 100 000

Look carefully at the above pattern and fill in:

100 000 x 10 = ______________________________________________________

Correct! 100 000 x 10 = 1 000 000

We read: 1 000 000 is one million

• In the notation column it looks like this:
 Million Hundred thousand Ten thousand Thousand Hundred Ten One M HTh TTh Th H T U 1 000 000 100 000 10 000 1 000 100 10 1
• Let’s read these big numbers:

4 721 568 is read as 4 million 721 thousand 568

Thus: Four million seven hundred and twenty one thousand five hundred and sixty eight

#### NOTE!

We group figures (digits) in threes from the right.

In the example the first space from the left tells us how many millions we have. The second space from the left indicates how many thousands there are.

E.g. 3 (million) 268 (thousand) 413

## 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:

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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?

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.

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