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Whole Numbers
In this article, we are learning about Whole Numbers as per the Primary 5 Maths level.
The learning objectives are:
- Reading and Writing Numbers
- Multiplying or Dividing by 10, 100 or 1000 and their multiples
1. Reading And Writing Numbers
Whole numbers include zero and counting numbers. They are without fractions. In Primary 5, we will learn Numbers up to 10 million.
Let’s place the digits in 675 840 in their respective place values.
We read 675 840 as six hundred and seventy-five thousand, eight hundred and forty.
The place value of the digit 6 is hundred thousands. The value of the digit 6 is 600 000.
The place value of the digit 7 is ten thousands. The value of the digit 7 is 70 000.
The place value of the digit 5 is thousands. The value of the digit 5 is 5000.
The place value of the digit 8 is hundreds. The value of the digit 8 is 800.
The place value of the digit 4 is tens. The value of the digit 4 is 40.
Remember the ‘s’ for the place values!
Let us try placing the digits in 9 675 840 in their respective place values.
We read 9 675 840 as nine million, six hundred and seventy-five thousand, eight hundred and forty.
The place value of the digit 9 is millions. The value of the digit 9 is 9 000 000.
It is a good habit to include spaces at the appropriate places when writing numbers in numerals.
Remember to include a comma and hyphen(s) at the appropriate places when writing numbers in words.
Question 1:
Write the following in numerals.
Solution:
Place the digits in a place value chart as shown below.
Three million, three hundred thousand, four hundred and thirty-five = 3 300 435
Answer:
3 300 435
Question 2:
Write the following number in numerals.
Solution:
Place the digits in a place value chart as shown below.
Answer:
8 450 207
Question 3:
Write the following in numerals.
Solution:
Place the digits in a place value chart as shown below.
Answer:
4 015 068
Question 4:
Write the following in words.
Solution:
Place the digits in a place value chart as shown below.
3 051 043 = Three million, fifty-one thousand and forty-three
Answer:
Three million, fifty-one thousand and forty-three
Question 5:
Write in words the following number.
Solution:
Place the digits in a place value chart as shown below.
7 250 025 = Seven million, two hundred and fifty thousand and twenty-five
Answer:
Seven million, two hundred and fifty thousand and twenty-five
Question 6:
Write the following in words.
Solution:
Place the digits in a place value chart as shown below.
4 325 630 = Four million, three hundred and twenty-five thousand, six hundred and thirty
Answer:
Four million, three hundred and twenty-five thousand, six hundred and thirty
2. Multiplying or Dividing by 10, 100 or 1000 and their multiples
Multiplying by 10, 100 or 1000
When we multiply a whole number by 10, we add one ‘0’ after the number.
Example:
5 × 10 = 50
When we multiply a whole number by 100, we add two ‘0’s after the number.
Example:
5 × 100 = 500
When we multiply a whole number by 1000, we add three ‘0’s after the number.
Example:
5 × 1000 = 5000
Question 1:
Match.
Solution:
Multiplying by the multiples of 10, 100 or 1000
Now let’s multiply a number by the multiples of 10, 100 or 1000.
When we multiply a whole number by a multiple of 10, we express the multiple of 10 as a product of a number and 10.
Example:
12 × 50 = 12 × 5 × 10
= 60 × 10
= 600
When we multiply a whole number by a multiple of 100, we express the multiple of 100 as a product of a number and 100.
Example:
12 x 500 = 12 × 5 × 100
= 60 × 100
= 6000
When we multiply a whole number by a multiple of 1000, we express the multiple of 1000 as a product of a number and 1000.
Example:
12 x 5000 = 12 × 5 × 1000
= 60 × 1000
= 60 000
Question 1:
Do the following multiplication.
- 27 × 1000 = __________
- 27 × 5000 = __________
Solution:
- 27 × 1000 = 27 000
- 27 × 5000 = 27 × 5 × 1000
= 135 × 1000
= 135 000
Answer:
- 27 000
- 135 000
Question 2:
Do the following multiplication.
319 × 6000 = _________
Solution:
319 x 6000 = 319 × 6 × 1000
= 1 914 000
Answer:
1 914 000
Question 3:
Do the following multiplication.
700 × 9000 = _________
Solution:
7 × 100 × 9 × 1000 = 7 × 9 × 100 × 1000
= 6 300 000
Answer:
6 300 000
Question 4:
Fill in the blanks.
- 12 × __________ = 12 000
- 12 × __________ = 120 000
Solution:
- 12 × 1000 = 12 000
- 12 × 10 000 = 120 000
Answer:
- 1000
- 10 000
Question 5:
Fill in the blanks
60 × __________ = 720
Solution:
60 × ________ = 720
60 × 12 = 720
Answer:
12
Dividing by 10, 100 or 1000
When we divide a whole number by 10, we remove one ‘0’ after the number.
Example:
70 000 ÷ 10 = 7000
When we divide a whole number by 100, we remove two ‘0’s after the number.
Example:
70 000 ÷ 100 = 700
When we divide a whole number by 1000, we remove three ‘0’s after the number.
Example:
70 000 ÷ 1000 = 70
Question 1:
Do the following division.
880 ÷ 10 = __________
Solution:
880 ÷ 10 = 88
Answer:
88
Question 2:
Do the following division.
293 000 ÷ 100 = __________
Solution:
293 000 ÷ 100 = 2930
Answer:
2930
Question 3:
Do the following division.
630 000 ÷ 1000 =__________
Solution:
630 000 ÷ 1000 = 630
Answer:
630
Dividing by the multiples of 10, 100 or 1000
Now let’s divide a number by the multiples of 10, 100 or 1000.
When we divide a whole number by a multiple of 10, we break the multiple of 10 into 10 and a number. We will divide by 10 first, followed by the number.
Example:
30 000 ÷ 60 = 30 000 ÷ 10 ÷ 6
= 3000 ÷ 6
= 500
When we divide a whole number by a multiple of 100, we break the multiple of 100 into 100 and a number. We will divide by 100 first, followed by the number.
Example:
30 000 ÷ 600 = 30 000 ÷ 100 ÷ 6
= 300 ÷ 6
= 50
When we divide a whole number by a multiple of 1000, we break the multiple of 1000 into 1000 and a number. We will divide by 1000 first, followed by the number.
Example:
30 000 \(\div\) 6000 = 30 000 ÷ 1000 ÷ 6
= 30 ÷ 6
= 5
Question 1:
Do the following division.
36 600 ÷ 60 =__________
Solution:
36 600 ÷ 60 = 36 600 ÷ 10 ÷ 6
= 3660 ÷ 6
= 610
Answer:
610
Question 2:
Do the following division.
44 800 ÷ 800 =__________
Solution:
44 800 ÷ 800 = 44 800 ÷ 100 ÷ 8
= 448 ÷ 8
= 56
Answer:
56
Question 3:
Do the following division.
630 000 ÷ 9000 =__________
Solution:
630 000 ÷ 9000 = 630 000 ÷ 1000 ÷ 9
= 630 ÷ 9
= 70
Answer:
70
Question 4:
Fill in the blanks with the correct answer.
8400 ÷ __________= 70
Solution:
8400 ÷ 70 = 8400 ÷ 10 ÷ 7
= 840 ÷ 7
= 120
Answer:
120
Conclusion
In this article, we learnt about the Whole Numbers as per the Primary 5 Math level. We learnt the following subtopics in Whole Numbers:
- Reading and Writing Numbers up to 10 million
- Multiplication and Division by 10, 100, or 1000 and their multiples.
Primary
Secondary
