Page 1
GrADe 6: MATheMATiCS [TerM 2] 125
Unit Whole n Umbers :
2
m Ulti Plic Ation 2.1 Extending multiplication facts
To do calculations such as 56 × 73 and 254 × 78, and to do
multiplication with bigger numbers such as 357 × 472 and 7 358 × 573,
you need to know basic multiplication facts such as 50 × 70 = 3 500
very well.
In this section, you will refresh your memory of multiplication facts.
1. For which of the following can you give the answers straight away?
Write down only those answers that you know immediately. You
can answer the others later.
(a) 2 × 7 (b) 3 × 5 (c) 6 × 7 (d) 70 × 10
(e) 8 × 90 (f) 6 × 4 (g) 6 × 8 (h) 6 × 9
A multiplication fact that you know can often help you to build
knowledge of another multiplication fact. Here are some examples:
If you know that 2 × 7 = 14, you also know that 7 × 2 = 14.
You can easily see that
2 × 70 = 140 and 70 × 2 = 140
2 × 700 = 1 400 and 700 × 2 = 1 400
2 × 7 000 = 14 000 and 7 000 × 2 = 14 000.
If you know that 2 × 70 = 140 and 70 × 2 = 140,
you can also easily see that
20 × 70 = 1 400 and 70 × 20 = 1 400
200 × 70 = 14 000 and 70 × 200 = 14 000
20 × 700 = 14 000 and 700 × 20 = 14 000
200 × 700 = 140 000 and 700 × 200 = 140 000, and so on.
You can double the answer of 2 × 7 = 14 to get 4 × 7 = 28 and then you
also know that 7 × 4 = 28.
Maths_English_LB_Grade6_Book.indb 125 2016/12/15 4:21:21 PM
Page 2
GrADe 6: MATheMATiCS [TerM 2] 125
Unit Whole n Umbers :
2
m Ulti Plic Ation 2.1 Extending multiplication facts
To do calculations such as 56 × 73 and 254 × 78, and to do
multiplication with bigger numbers such as 357 × 472 and 7 358 × 573,
you need to know basic multiplication facts such as 50 × 70 = 3 500
very well.
In this section, you will refresh your memory of multiplication facts.
1. For which of the following can you give the answers straight away?
Write down only those answers that you know immediately. You
can answer the others later.
(a) 2 × 7 (b) 3 × 5 (c) 6 × 7 (d) 70 × 10
(e) 8 × 90 (f) 6 × 4 (g) 6 × 8 (h) 6 × 9
A multiplication fact that you know can often help you to build
knowledge of another multiplication fact. Here are some examples:
If you know that 2 × 7 = 14, you also know that 7 × 2 = 14.
You can easily see that
2 × 70 = 140 and 70 × 2 = 140
2 × 700 = 1 400 and 700 × 2 = 1 400
2 × 7 000 = 14 000 and 7 000 × 2 = 14 000.
If you know that 2 × 70 = 140 and 70 × 2 = 140,
you can also easily see that
20 × 70 = 1 400 and 70 × 20 = 1 400
200 × 70 = 14 000 and 70 × 200 = 14 000
20 × 700 = 14 000 and 700 × 20 = 14 000
200 × 700 = 140 000 and 700 × 200 = 140 000, and so on.
You can double the answer of 2 × 7 = 14 to get 4 × 7 = 28 and then you
also know that 7 × 4 = 28.
Maths_English_LB_Grade6_Book.indb 125 2016/12/15 4:21:21 PM
126 UNiT 1: WhOLe NUMBerS 126 UNiT 2: WhOLe NUMBerS: MULTiPLiCATiON
2. Continue to think of all the new multiplication facts that you can
make from 2 × 7 = 14 and record them in a table like the one below.
Facts that can be easily formed by building on 2 × 7 = 14
× 7 70 700 7 000
2 14 140 1 400 14 000
20 1 400 14 000
200 14 000 140 000
2 000
4 28
40
400
4 000
3. See which facts you can build from 3 × 7 = 21, and record your
results in a table like the one above.
4. See which facts you can build from 4 × 6 = 24, and record your
results in a table like the one above.
You saw earlier that in order to build new facts from 2 × 7 = 14, you can
double the answer to get 4 × 7 = 28, and then build further from there.
Here is another way to build on a known fact:
If you know that 4 × 7 = 28, you can add another 7 to get 5 × 7 = 35.
If you know that 6 × 8 = 48, you can add another 8 to get 7 × 8 = 56.
5. Now use addition, as explained above, to build new facts from each
of the following:
(a) 7 × 7 = 49 (b) 5 × 6 = 30 (c) 2 × 9 = 18
(d) 5 × 7 = 35 (e) 7 × 9 = 63 (f) 6 × 4 = 24
6. Look again at the work you did in question 1. Were there any
questions that you could not answer? Try to work out those answers
now.
Maths_English_LB_Grade6_Book.indb 126 2016/12/15 4:21:21 PM
Page 3
GrADe 6: MATheMATiCS [TerM 2] 125
Unit Whole n Umbers :
2
m Ulti Plic Ation 2.1 Extending multiplication facts
To do calculations such as 56 × 73 and 254 × 78, and to do
multiplication with bigger numbers such as 357 × 472 and 7 358 × 573,
you need to know basic multiplication facts such as 50 × 70 = 3 500
very well.
In this section, you will refresh your memory of multiplication facts.
1. For which of the following can you give the answers straight away?
Write down only those answers that you know immediately. You
can answer the others later.
(a) 2 × 7 (b) 3 × 5 (c) 6 × 7 (d) 70 × 10
(e) 8 × 90 (f) 6 × 4 (g) 6 × 8 (h) 6 × 9
A multiplication fact that you know can often help you to build
knowledge of another multiplication fact. Here are some examples:
If you know that 2 × 7 = 14, you also know that 7 × 2 = 14.
You can easily see that
2 × 70 = 140 and 70 × 2 = 140
2 × 700 = 1 400 and 700 × 2 = 1 400
2 × 7 000 = 14 000 and 7 000 × 2 = 14 000.
If you know that 2 × 70 = 140 and 70 × 2 = 140,
you can also easily see that
20 × 70 = 1 400 and 70 × 20 = 1 400
200 × 70 = 14 000 and 70 × 200 = 14 000
20 × 700 = 14 000 and 700 × 20 = 14 000
200 × 700 = 140 000 and 700 × 200 = 140 000, and so on.
You can double the answer of 2 × 7 = 14 to get 4 × 7 = 28 and then you
also know that 7 × 4 = 28.
Maths_English_LB_Grade6_Book.indb 125 2016/12/15 4:21:21 PM
126 UNiT 1: WhOLe NUMBerS 126 UNiT 2: WhOLe NUMBerS: MULTiPLiCATiON
2. Continue to think of all the new multiplication facts that you can
make from 2 × 7 = 14 and record them in a table like the one below.
Facts that can be easily formed by building on 2 × 7 = 14
× 7 70 700 7 000
2 14 140 1 400 14 000
20 1 400 14 000
200 14 000 140 000
2 000
4 28
40
400
4 000
3. See which facts you can build from 3 × 7 = 21, and record your
results in a table like the one above.
4. See which facts you can build from 4 × 6 = 24, and record your
results in a table like the one above.
You saw earlier that in order to build new facts from 2 × 7 = 14, you can
double the answer to get 4 × 7 = 28, and then build further from there.
Here is another way to build on a known fact:
If you know that 4 × 7 = 28, you can add another 7 to get 5 × 7 = 35.
If you know that 6 × 8 = 48, you can add another 8 to get 7 × 8 = 56.
5. Now use addition, as explained above, to build new facts from each
of the following:
(a) 7 × 7 = 49 (b) 5 × 6 = 30 (c) 2 × 9 = 18
(d) 5 × 7 = 35 (e) 7 × 9 = 63 (f) 6 × 4 = 24
6. Look again at the work you did in question 1. Were there any
questions that you could not answer? Try to work out those answers
now.
Maths_English_LB_Grade6_Book.indb 126 2016/12/15 4:21:21 PM
GrADe 6: MATheMATiCS [TerM 2] 127
2.2 Summarise and practise multiplication facts
1. Complete this table.
× 6 9 4 10 3 2 5 8 7
7 42
3 12
8
5 45
9
2 10
6
4
10
2. Now complete this table.
× 4 90 60 7 30 8 5 20 10
50
3
6
70
40
9
80
4
10
When you have completed the tables in questions 1 and 2, answer
question 3.
Maths_English_LB_Grade6_Book.indb 127 2016/12/15 4:21:22 PM
Page 4
GrADe 6: MATheMATiCS [TerM 2] 125
Unit Whole n Umbers :
2
m Ulti Plic Ation 2.1 Extending multiplication facts
To do calculations such as 56 × 73 and 254 × 78, and to do
multiplication with bigger numbers such as 357 × 472 and 7 358 × 573,
you need to know basic multiplication facts such as 50 × 70 = 3 500
very well.
In this section, you will refresh your memory of multiplication facts.
1. For which of the following can you give the answers straight away?
Write down only those answers that you know immediately. You
can answer the others later.
(a) 2 × 7 (b) 3 × 5 (c) 6 × 7 (d) 70 × 10
(e) 8 × 90 (f) 6 × 4 (g) 6 × 8 (h) 6 × 9
A multiplication fact that you know can often help you to build
knowledge of another multiplication fact. Here are some examples:
If you know that 2 × 7 = 14, you also know that 7 × 2 = 14.
You can easily see that
2 × 70 = 140 and 70 × 2 = 140
2 × 700 = 1 400 and 700 × 2 = 1 400
2 × 7 000 = 14 000 and 7 000 × 2 = 14 000.
If you know that 2 × 70 = 140 and 70 × 2 = 140,
you can also easily see that
20 × 70 = 1 400 and 70 × 20 = 1 400
200 × 70 = 14 000 and 70 × 200 = 14 000
20 × 700 = 14 000 and 700 × 20 = 14 000
200 × 700 = 140 000 and 700 × 200 = 140 000, and so on.
You can double the answer of 2 × 7 = 14 to get 4 × 7 = 28 and then you
also know that 7 × 4 = 28.
Maths_English_LB_Grade6_Book.indb 125 2016/12/15 4:21:21 PM
126 UNiT 1: WhOLe NUMBerS 126 UNiT 2: WhOLe NUMBerS: MULTiPLiCATiON
2. Continue to think of all the new multiplication facts that you can
make from 2 × 7 = 14 and record them in a table like the one below.
Facts that can be easily formed by building on 2 × 7 = 14
× 7 70 700 7 000
2 14 140 1 400 14 000
20 1 400 14 000
200 14 000 140 000
2 000
4 28
40
400
4 000
3. See which facts you can build from 3 × 7 = 21, and record your
results in a table like the one above.
4. See which facts you can build from 4 × 6 = 24, and record your
results in a table like the one above.
You saw earlier that in order to build new facts from 2 × 7 = 14, you can
double the answer to get 4 × 7 = 28, and then build further from there.
Here is another way to build on a known fact:
If you know that 4 × 7 = 28, you can add another 7 to get 5 × 7 = 35.
If you know that 6 × 8 = 48, you can add another 8 to get 7 × 8 = 56.
5. Now use addition, as explained above, to build new facts from each
of the following:
(a) 7 × 7 = 49 (b) 5 × 6 = 30 (c) 2 × 9 = 18
(d) 5 × 7 = 35 (e) 7 × 9 = 63 (f) 6 × 4 = 24
6. Look again at the work you did in question 1. Were there any
questions that you could not answer? Try to work out those answers
now.
Maths_English_LB_Grade6_Book.indb 126 2016/12/15 4:21:21 PM
GrADe 6: MATheMATiCS [TerM 2] 127
2.2 Summarise and practise multiplication facts
1. Complete this table.
× 6 9 4 10 3 2 5 8 7
7 42
3 12
8
5 45
9
2 10
6
4
10
2. Now complete this table.
× 4 90 60 7 30 8 5 20 10
50
3
6
70
40
9
80
4
10
When you have completed the tables in questions 1 and 2, answer
question 3.
Maths_English_LB_Grade6_Book.indb 127 2016/12/15 4:21:22 PM
128 UNiT 1: WhOLe NUMBerS 128 UNiT 2: WhOLe NUMBerS: MULTiPLiCATiON
3. Calculate.
(a) 41 × 7 (b) 94 × 50
(c) 37 × 40 (d) 97 × 80
4. Now complete this table.
× 40 900 60 70 300 80 500 20 100
50
30
600
70
400
90
800
40
100
When you have completed all three tables in this section, you can answer
question 5.
5. Show how you can use the three tables to calculate the following:
(a) 900 × 40 (b) 940 × 70
(c) 320 × 800 (d) 1 10 × 30
(e) 540 × 90 (f) 170 × 800
2.3 Products and factors
You saw in the previous section how important it is that you know the
“times tables” well. Every multiplication fact that you know can help
you to build knowledge of other multiplication facts. In this section you
will learn more multiplication skills.
Start with questions 1 to 5. Answer all five questions.
The multiplication facts in
the tables you made can
be helpful.
Maths_English_LB_Grade6_Book.indb 128 2016/12/15 4:21:22 PM
Page 5
GrADe 6: MATheMATiCS [TerM 2] 125
Unit Whole n Umbers :
2
m Ulti Plic Ation 2.1 Extending multiplication facts
To do calculations such as 56 × 73 and 254 × 78, and to do
multiplication with bigger numbers such as 357 × 472 and 7 358 × 573,
you need to know basic multiplication facts such as 50 × 70 = 3 500
very well.
In this section, you will refresh your memory of multiplication facts.
1. For which of the following can you give the answers straight away?
Write down only those answers that you know immediately. You
can answer the others later.
(a) 2 × 7 (b) 3 × 5 (c) 6 × 7 (d) 70 × 10
(e) 8 × 90 (f) 6 × 4 (g) 6 × 8 (h) 6 × 9
A multiplication fact that you know can often help you to build
knowledge of another multiplication fact. Here are some examples:
If you know that 2 × 7 = 14, you also know that 7 × 2 = 14.
You can easily see that
2 × 70 = 140 and 70 × 2 = 140
2 × 700 = 1 400 and 700 × 2 = 1 400
2 × 7 000 = 14 000 and 7 000 × 2 = 14 000.
If you know that 2 × 70 = 140 and 70 × 2 = 140,
you can also easily see that
20 × 70 = 1 400 and 70 × 20 = 1 400
200 × 70 = 14 000 and 70 × 200 = 14 000
20 × 700 = 14 000 and 700 × 20 = 14 000
200 × 700 = 140 000 and 700 × 200 = 140 000, and so on.
You can double the answer of 2 × 7 = 14 to get 4 × 7 = 28 and then you
also know that 7 × 4 = 28.
Maths_English_LB_Grade6_Book.indb 125 2016/12/15 4:21:21 PM
126 UNiT 1: WhOLe NUMBerS 126 UNiT 2: WhOLe NUMBerS: MULTiPLiCATiON
2. Continue to think of all the new multiplication facts that you can
make from 2 × 7 = 14 and record them in a table like the one below.
Facts that can be easily formed by building on 2 × 7 = 14
× 7 70 700 7 000
2 14 140 1 400 14 000
20 1 400 14 000
200 14 000 140 000
2 000
4 28
40
400
4 000
3. See which facts you can build from 3 × 7 = 21, and record your
results in a table like the one above.
4. See which facts you can build from 4 × 6 = 24, and record your
results in a table like the one above.
You saw earlier that in order to build new facts from 2 × 7 = 14, you can
double the answer to get 4 × 7 = 28, and then build further from there.
Here is another way to build on a known fact:
If you know that 4 × 7 = 28, you can add another 7 to get 5 × 7 = 35.
If you know that 6 × 8 = 48, you can add another 8 to get 7 × 8 = 56.
5. Now use addition, as explained above, to build new facts from each
of the following:
(a) 7 × 7 = 49 (b) 5 × 6 = 30 (c) 2 × 9 = 18
(d) 5 × 7 = 35 (e) 7 × 9 = 63 (f) 6 × 4 = 24
6. Look again at the work you did in question 1. Were there any
questions that you could not answer? Try to work out those answers
now.
Maths_English_LB_Grade6_Book.indb 126 2016/12/15 4:21:21 PM
GrADe 6: MATheMATiCS [TerM 2] 127
2.2 Summarise and practise multiplication facts
1. Complete this table.
× 6 9 4 10 3 2 5 8 7
7 42
3 12
8
5 45
9
2 10
6
4
10
2. Now complete this table.
× 4 90 60 7 30 8 5 20 10
50
3
6
70
40
9
80
4
10
When you have completed the tables in questions 1 and 2, answer
question 3.
Maths_English_LB_Grade6_Book.indb 127 2016/12/15 4:21:22 PM
128 UNiT 1: WhOLe NUMBerS 128 UNiT 2: WhOLe NUMBerS: MULTiPLiCATiON
3. Calculate.
(a) 41 × 7 (b) 94 × 50
(c) 37 × 40 (d) 97 × 80
4. Now complete this table.
× 40 900 60 70 300 80 500 20 100
50
30
600
70
400
90
800
40
100
When you have completed all three tables in this section, you can answer
question 5.
5. Show how you can use the three tables to calculate the following:
(a) 900 × 40 (b) 940 × 70
(c) 320 × 800 (d) 1 10 × 30
(e) 540 × 90 (f) 170 × 800
2.3 Products and factors
You saw in the previous section how important it is that you know the
“times tables” well. Every multiplication fact that you know can help
you to build knowledge of other multiplication facts. In this section you
will learn more multiplication skills.
Start with questions 1 to 5. Answer all five questions.
The multiplication facts in
the tables you made can
be helpful.
Maths_English_LB_Grade6_Book.indb 128 2016/12/15 4:21:22 PM
GrADe 6: MATheMATiCS [TerM 2] 129
1. What is the easiest way to calculate 2 × 17 × 5?
2. Ben buys 5 bags of bananas. Each bag has 4 bunches of bananas
with 3 bananas in each bunch.
(a) How many bananas does Ben buy?
(b) Write down the calculation plan to calculate the number of
bananas.
3. (a) Siba buys 4 boxes of beads. In each box there are 10 packets
and every packet has 15 beads. How many beads does she
buy? Write down your calculation plan to calculate the number
of beads.
(b) Marie buys 10 boxes of beads. In each box there are 15
packets and every packet has 4 beads. How many beads does
she buy? Write down your calculation plan to calculate the
number of beads.
(c) Jeff buys 15 boxes of beads. In each box there are 10 packets
and every packet has 4 beads. How many beads does he
buy? Write down your calculation plan to calculate the number
of beads.
4. Compare your three calculation plans for question 3. What do you
notice?
If we multiply three or more
numbers we can rearrange the
numbers to change the order in
which we multiply. It does not
change the answer. This is a
property of multiplication.
5. Calculate the following. Rearrange the numbers to make it easier.
(a) 50 × 37 × 2
(b) 4 × 68 × 25
(c) 3 × 74 × 10
(d) 5 × 22 × 8
When you have to
multiply three or more
numbers, you may
rearrange the numbers
to make the calculation
easier.
Maths_English_LB_Grade6_Book.indb 129 2016/12/15 4:21:22 PM
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