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• GETIntPhaseMaths

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

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# To perform mental calculations

Module by: Siyavula Uploaders. E-mail the author

## Memorandum

1. Length of your desk = cm

Your own height = cm / m

Width of the class = m

Length of your pencil = cm / mm

2. km

• 1 000
• 1 000
• 100
• 10

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

Let us see how well you can remember the work that was done in the previous module. Complete this mental calculation test as quickly and as accurately as possible:

1. 11 x 8 = ___________________________

2. 11 x 0,8 = _________________________

3. 1,1 x 0,8 = _________________________

4. 1,1 x 10 = _________________________

5. 1,1 x 100 = ________________________

6. 11 ÷ 10 = _________________________

7. 11 ÷ 100 = _________________________

8. _________________________ x 1 000 = 111

9. 1 m = _________________________ mm

10. 1 cm = _________________________ mm

11. 1 km = _________________________ m

12. 1 km = _________________________ mm

13. 2 x 104 = _________________________

14. 0,4 x 20 = _________________________

15. Double 19,5 : _______________________

## 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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