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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

# Performing mental calculations

Module by: Siyavula Uploaders. E-mail the author

1. 0,2

2. 0,32

3. 2,17

4. 59,8

5. 5 980

6. 1,984

7. 39,6

8. 9,75

9. 4 700 mm

10. 10,5 ℓ

11. 6 m

12. 7,2 ℓ

13. 1,75 kg

14. 2 918 mℓ

15. 0,017 km

## Content

### ACTIVITY: Performing mental calculations [LO 1.9]

It is time to see if you can improve your skill in mental calculation! Apply the knowledge that you have already gained and note how quickly and accurately you are able to complete this mental calculation test.

1. 200 ÷ 1 000 = _________________________________________________

2. 32 ÷ 100 = ___________________________________________________

3. 217 ÷ 100 = __________________________________________________

4. 5,98 × 10 = ___________________________________________________

5. 59,8 × 100 = __________________________________________________

6. 198,4 ÷ 100 = _________________________________________________

7. Double 19,8 : __________________________________________________

8. Halve 19,5 : ___________________________________________________

9. 5 m – 300 mm = _______________________________________________

10. 12 ℓ – 1,5 ℓ = _________________________________________________

11. 3,8 m + 2,2 m = _______________________________________________

12. 2,4 ℓ × 3 = ___________________________________________________

13. of 3,5 kg = __________________________________________________

14. 2,918 ℓ = __________________________________________________ mℓ

15. 17 m = ____________________________________________________ km

## 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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