<< Chapter < Page | Chapter >> Page > |
If you as educator do not want to do halving just after doubling, leave it for the moment and do it later. However, make very sure that the slower learners in particular understand and have mastered the process of doubling before you do halving. Only do halving of even numbers at first.
It is important for the learners to know that 10 ÷ 2 can have 2 different meanings: division or grouping.
Look at the following two problems:
Divide 10 apples between 2 children so that they receive the same amount.
10 ¸ 2 = 5 Each receives 5 apples.
I have 10 apples and give 2 to each child. How many children were there?
10 ¸ 2 = 5 There were 5 children.
The number sentence is the same, but the presentation differs.
Double means: Add just as many.
You must add the same number twice (2x).
Double 5: _________________________ (Think like this: 5 + 5 ) That is 2 x 5.
There are 2 groups of 10.
Number sentence: 2 x 10 = ________________________
LO 1.10 |
2 x 4 = 8 | Change them: 4 x 2 = 8 |
2 x 10 = _____ | ____ x ____ = _____ |
2 x 3 = _____ | ____ x ____ = _____ |
2 x 8 = _____ | ____ x ____ = _____ |
2 x 2 = _____ | ____ x ____ = _____ |
2 x 5 = _____ | ____ x ____ = _____ |
2 x 1 = _____ | ____ x ____ = _____ |
2 x 6 = _____ | ____ x ____ = _____ |
2 x 9 = _____ | ____ x ____ = _____ |
2 x 7 = _____ | ____ x ____ = _____ |
LO 1.9 |
Think like this: 2 + 2 + 2 + 2 + 2
Number sentence: 5 x 2 = ___________ or 2 x 5 = ___________
There are___________ wheels.
Number sentence: 8 x 2 = ___________ or ___________ x ___________ =
There are___________ wheels.
Number sentence: 20 x 2 = ________ or ________ x _______. = ________
She has________ c in her purse. Draw the money.
LO 1.8 |
Half of 10 is 5.
We halved the number 10.
Halving means: divide into two equal parts.
Use the sums above to help you!!
LO 1.10 |
Each gets 5 apples.
This is the same as halving. Number sentence: 10 ÷ 2 = 5
There are___________________________ bicycles.
Number sentence: 10 ÷ 2 = 5
Now you can count how many rabbits are hiding behind the bush. 12 ÷ 2 =
____________________________ There are _________________________ rabbits.
LO 1.7 |
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 1.7: We know this when the learner solves and explains solutions to practical problems that involve equal sharing and grouping and that lead to solutions that also include unitary and nonunitary fractions (e.g. 1¼1 , ¾4);
Assessment Standard 1.8: We know this when the learner can perform calculations, using appropriate symbols, to solve problems involving:
1.8.1 addition and subtraction of whole numbers with at least 3 digits;
1.8.2 multiplication of at least whole 2-digit by 1-digit numbers;
1.8.3 division of at least whole 2-digit by 1-digit numbers;
Assessment Standard 1.9: We know this when the learner performs mental calculations involving:
1.9.1 addition and subtraction for numbers to at least 50;
1.9.2 multiplication of whole numbers with solutions to at least 50;
Assessment Standard 1.10: We know this when the learner uses the following techniques:
1.10.1 building up and breaking down numbers;
1.10.2 doubling and halving;
1.10.3 number-lines;
1.10.4 rounding off in tens.
Notification Switch
Would you like to follow the 'Mathematics grade 3' conversation and receive update notifications?