GET DIRECTORATE Page 1 of 15 Grade 5 Multiplication,ratio and rate TOPIC: MULTIPLICATION, RATIO AND RATE DAY 1 CLASS ACTIVITY: Complete the activities in your Maths workbook. Use the memorandum to check your work. Mental Maths 1. Complete the following exercise in your workbook. Write down only the answers. 30 × 8 = 30 × 5 = 90 x 10 = 20 × 9 = 80 × 8 = 60 x 6 = 80 × 6 = 20 × 7 = 50 x 5 = 90 × 7 = 20 × 4 = 50 x 50 = 30 × 2 = 90 × 2 = 80 x 9 = 20 × 6 = 90 x 20 = 60 x 40 = Multiply 3-digit numbers with 1-digit numbers. Study the following example: 2. Use the above method and do the following in your workbook. (a) 563 × 7 (b) 6 × 378 (c) 7 × 493 (d) 908 × 8 Watch the following video (3- digit x 1-digit) if you still do not understand the method. Click on the video icon Break up the first number. 347 x 8 can be calculated as follows: 347 x 8 = (300 + 40 + 7) x 8 Thus, 347 x 8 = 300 x 8 + 40 x 8 + 7 x 8 = 2 400 + 320 + 56 = 2 000 + 400 + 300 + 20 + 50 + 6 = 2 766 MATHEMATICS GRADE 5
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GET DIRECTORATE
Page 1 of 15
Grade 5 Multiplication,ratio and rate
TOPIC: MULTIPLICATION, RATIO AND RATE
DAY 1
CLASS ACTIVITY: Complete the activities in your Maths workbook. Use the
memorandum to check your work.
Mental Maths
1. Complete the following exercise in your workbook. Write down only the answers.
30 × 8 = 30 × 5 = 90 x 10 =
20 × 9 = 80 × 8 = 60 x 6 =
80 × 6 = 20 × 7 = 50 x 5 =
90 × 7 = 20 × 4 = 50 x 50 =
30 × 2 = 90 × 2 = 80 x 9 =
20 × 6 = 90 x 20 = 60 x 40 =
Multiply 3-digit numbers with 1-digit numbers. Study the following example:
2. Use the above method and do the following in your workbook.
(a) 563 × 7 (b) 6 × 378
(c) 7 × 493 (d) 908 × 8
Watch the following video (3- digit x 1-digit) if you still do not understand the method.
Click on the video icon
Break up the first number.
347 x 8 can be calculated as follows:
347 x 8 = (300 + 40 + 7) x 8
Thus, 347 x 8 = 300 x 8 + 40 x 8 + 7 x 8
= 2 400 + 320 + 56
= 2 000 + 400 + 300 + 20 + 50 + 6
= 2 766
MATHEMATICS
GRADE 5
GET DIRECTORATE
Page 2 of 15
Grade 5 Multiplication,ratio and rate
HOMEWORK: Complete the activities in your Maths workbook. Use the memorandum to
check your work.
3. One hotel has 238 rooms. How many rooms are there in 7 such hotels?
4. Jane needs to feed eight two-week-old baby goats 375 ml of milk each, four times a day.
How much milk does she need every day? Give your answer in milliliters.
5. A bag of onions has a mass of 875 g. Calculate the total mass of eight bags of onions.
Give your answer in kilograms.
MEMORANDUM: CLASSWORK
1.
30 × 8 = 240 30 × 5 = 150 90 x 10 = 900
20 × 9 =180 80 × 8 = 640 60 x 6 = 360
80 × 6 = 480 20 × 7 = 140 50 x 5 = 250
90 × 7 = 630 20 × 4 = 80 50 x 50 = 2 500
30 × 2 = 60 90 × 2 = 180 80 x 9 = 720
20 × 6 = 120 90 x 20 = 1 800 60 x 40 = 2
2. (a) 563 × 7 = 500 x 7 + 60 x 7 + 3 x 7
= 3 500 + 420 + 21
= 3 000 + 500 +400 + 20 + 20 + 1
= 3 941
(b) 6 × 378 = 6 x 300 + 6 x 70 + 6 x 8
= 1 800 + 420 + 48
=1 000 + 800 + 400 +20 + 40 + 8
= 2 200 +60 + 8
= 2 268
(c) 7 × 493 = 7 x 400 + 7 x 90 + 7 x 3
= 2 800 +630 + 63
= 2 000 + 800 + 600 + 30 + 60 + 3
= 3 493
(d) 908 × 8 = 900 x 8 + 8 x 8
= 7 200 + 64
= 7 000 + 200 + 60 + 4
= 7 264
MEMORANDUM: HOMEWORK 3. Number of rooms: 238 x 7 = 1 666
4. Quantity of milk: 4 x 8 x 375 = 12 000 ml
5. Mass: 875 x 8 = 7 000 g = 7 kg
GET DIRECTORATE
Page 3 of 15
Grade 5 Multiplication,ratio and rate
CLASS ACTIVITY: Complete the activities in your Maths workbook. Use the
memorandum to check your work.
Mental Maths
1. Complete the following exercise in your workbook. Write down only the answers
30 × 80 = 30 × 20 = 80 × 800 =
20 × 90 = 30 × 50 = 90 × 200 =
80 × 60 = 20 × 7= 90 × 50 =
90 × 70 = 80 × 10 = 90 x 500 =
30 × 10 = 90 × 80 = 80 x 70 =
20 × 40 = 20 × 600 = 90 x 100 =
Today you are going to learn how to multiply a 3-digit number with a 2-digit number
Study the following example:
Example: 143 x 24 = 3 432
1 4 3
x 2 4
1 2 4 x 3
1 6 0 4 x 40
4 0 0 4 x 100
6 0 20 x 3
8 0 0 20 x 40
2 0 0 0 20 x 100
3 4 3 2
Use the method above and do the following in your workbook.
(a) 384 × 76 (b) 34 × 328
Watch the following video (3- digit x 2-digit_vertical column method) if you still do not
understand the method.
Click on the video icon
HOMEWORK:
Do activity in your Maths workbook. Use the memorandum to check your work.
If you really want to fully understand this method, you can do the
following activity in your DBE workbook. Exercise 44a page 129 nr 3a and 3b.
Use method as explained in example 2.
DAY 2
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Page 4 of 15
Grade 5 Multiplication,ratio and rate
MEMORANDUM: CLASSWORK
1.
30 × 80 = 2 400 30 × 20 = 600 80 × 800 = 64 000
20 × 90 = 1 800 30 × 50 = 1 500 90 × 200 = 18 000
80 × 60 = 4 800 20 × 7 = 140 90 × 50 = 4 500
90 × 70 = 6 300 80 × 10 = 800 90 x 500 = 45 000
30 × 10 = 300 90 × 80 = 7200 80 x 70 = 5 600
20 × 40 = 800 20 × 600 = 12 000 90 x 100 = 9 000
2a. 384 × 76 = 29 184
3 8 4
x 7 6
2 4 6 x 4
4 8 0 6 x 80
1 8 0 0 6 x 300
2 8 0 70 x 4
5 6 0 0 70 x 80
2 1 0 0 0 70 x 300
2 9 1 8 4
2b. 34 × 328 = 11 152
3 2 8
3 4
3 2 4 x 8
8 0 4 x 20
1 2 0 0 4 x 300
2 4 0 30 x 8
6 0 0 30 x 20
9 0 0 0 30 x 300
1 1 1 5 2
GET DIRECTORATE
Page 5 of 15
Grade 5 Multiplication,ratio and rate
HOMEWORK: MEMORANDUM -DBE WORKBOOK EX 44A PAGE 3a. 168 x 34 = 5 712
1 6 8
3 4
3 2 4 x 8
2 4 0 4 x 60
4 0 0 4 x 100
2 4 0 30 x 8
1 8 0 0 30 x 60
3 0 0 0 30 x 100
5 7 1 2 3b. 219 x 49 = 10 731
2 1 9
4 9
8 1 9 x 9
9 0 9 x 10
1 8 0 0 9 x 200
3 6 0 40 x 9
4 0 0 40 x 10
8 0 0 0 40 x 200
1 0 7 3 1
GET DIRECTORATE
Page 6 of 15
Grade 5 Multiplication,ratio and rate
CLASS ACTIVITY: Complete the activities in your workbook. Use the memorandum to check your work. Mental Maths
1. Complete the following exercise in your workbook. Write down only the answers.
30 × 80 = 80 × 70 = 20 × 700 =
20 × 90 = 90 × 80 = 900 × 100=
80 × 60 = 30 × 200 = 800× 10 =
90 × 70 = 30 × 500 = 900 × 5 =
30 × 10 = 20 × 600 = 90 × 200 =
20 × 40 = 80 × 800 =
Today we are going to use another method to multiply a 3-digit number with a 2-digit
number. This method is called the box method or area model.
Look at the following example:
143 x 24 = 3 432
x 100 40 3 Add the numbers
20 2 000 800 60 2 860 (2000 + 800 + 60)
4 400 160 12 572 (400 + 160 +12)
2 400 960 72 3 432 (2 400 + 960 + 72)
2. Use the method above and do the following in your workbook.
(a) 324 × 23 (b) 415 x 36
Watch the following video (3- digit x 2-digit_area model) if you still do not understand the method.
Click on the video icon
Break up 143 and 24
DAY 3
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Page 7 of 15
Grade 5 Multiplication,ratio and rate
HOMEWORK
1. If you really want to fully understand this method, you can do the
Following activity in your DBE workbook.
Exercise 49 page 140 nr 1a and 1b
Use the table method (also called the box method or area model)
2. The entrance fee for a concert is R48 for adults. Tickets are sold at the door. How much
money is taken at the door if 467 adults attend the concert?
3.(a) On a strawberry farm, there are 546 strawberry plants in each bed. How many plants are
there altogether in 34 strawberry beds?
(b) Strawberry jam is also produced on the farm and packed in boxes of 48 jars each. How