Facilitator’s Guide G04 ~ Mathematics
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Unit
Example: Refilwe loves to play with marbles. She has 12 marbles in her marble bag. During a competition, she loses 3 marbles. How many does she have left?
12 – 3 = ?
If you solve the number sentence:
12 – 3 = 9 Refilwe has 9 marbles left.
Write a few number sentences on your own.
ACTIVITY 6 1.
Write a number sentence for each of the statements or questions. Question
1.1 1.2 1.3 1.4 1.5
Mr Smith has 6 pencils. He picks up another 2 pencils on the playground. How many pencils does Mr Smith have altogether?
4 red birds sit on a branch. After a little while, 6 blue birds arrive and also sit on the branch. How many birds are sitting on the branch now? Lilly has 9 sweets. Lucy does not have any sweets. How many more sweets does Lilly have than Lucy?
Luke puts 15 flowers in a vase. 5 of the flowers wilt. How many flowers does Luke have left? Jo has 3 cards less than James. James has 18 cards. How many cards does Jo have?
Answer 6+2=8
4 + 6 = 10 9–0=9 15 – 5 = 10 18 – 3 = 15
Number sentences are not only represented with words, but can also be shown without using any words. You can solve and complete number sentences by: • inspection • trial and improvement • checking the solution by substitution
Let us look at solving number sentences by inspection.
The inspection method is another name for ‘guess the answer’. If you look at a number sentence and
must find the answer without making calculations, you will use the inspection method. In maths we only solve simple number sentences by inspection.
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