# Connexions

You are here: Home » Content » Mathematics Grade 6 » To perform mental calculations

### Lenses

What is a lens?

#### 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.

#### In these lenses

• GETIntPhaseMaths

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

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

Click the "GETIntPhaseMaths" link to see all content selected in this lens.

Click the tag icon to display tags associated with this content.

### Recently Viewed

This feature requires Javascript to be enabled.

### Tags

(What is a tag?)

These tags come from the endorsement, affiliation, and other lenses that include this content.

Inside Collection (Course):

Course by: Siyavula Uploaders. E-mail the author

# To perform mental calculations

Module by: Siyavula Uploaders. E-mail the author

## Memorandum

1. 100

2. 10 000

3. 4

4. 8

5. 27

6. 125

7. 9

8. 4

9. 2

10. 20

11. 9

12. 3

13. 7

14. 100 + 100 000 = 100 100

15. 22

## Content

### ACTIVITY: To perform mental calculations [LO 1.9]

By this time you should be quite bright and quick when working with numbers. Let's see how you perform in the next mental calculation test! Try to complete it within three minutes:

1. 102 = ______________________

2. 104 = ______________________

3. 22 = ______________________

4. 23 = ______________________

5. 33 = ______________________

6. 53 = ______________________

7. ______________________2 = 81

8. ______________________.3 = 64

9. 3 × 5 × ______________________ = 30

10. 0,3 × 5 × ______________________ = 30

11. 3 × ______________________ = 27

12. 3______________________ = 27

13. 102 × 105 = 10______________________

14. 102 + 105 = ______________________

15. 29 × 22 = (30 × 22) – __________________

## 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.

## Content actions

PDF | EPUB (?)

### What is an EPUB file?

EPUB is an electronic book format that can be read on a variety of mobile devices.

PDF | EPUB (?)

### What is an EPUB file?

EPUB is an electronic book format that can be read on a variety of mobile devices.

#### Collection to:

My Favorites (?)

'My Favorites' is a special kind of lens which you can use to bookmark modules and collections. 'My Favorites' can only be seen by you, and collections saved in 'My Favorites' can remember the last module you were on. You need an account to use 'My Favorites'.

| 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

#### Module to:

My Favorites (?)

'My Favorites' is a special kind of lens which you can use to bookmark modules and collections. 'My Favorites' can only be seen by you, and collections saved in 'My Favorites' can remember the last module you were on. You need an account to use 'My Favorites'.

| 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