Reading, Writing and Comparing Whole Numbers Beyond 1,000,000
Primary 6 · Mathematics
Reading, Writing and Comparing Whole Numbers Beyond 1,000,000
Lesson 1 of 6
30 min
Let's begin
In 2022 Rwanda counted every person in the country. The census found 13 246 394 people. Uwase read the number to her class and got stuck halfway through.
By the end of this lesson you will be able to say what every digit in a number like that is worth.
We split a big number into groups of three digits, starting from the right. Each group is called a period. The periods are ones, thousands, millions and billions. Every period has its own hundreds, tens and ones.
In Rwanda we leave a small space between the groups: 13 246 394. Some books use commas instead: 13,246,394. Both mean the same number.
| Millions | Thousands | Ones | |||||
|---|---|---|---|---|---|---|---|
| Ten millions | Millions | Hundred thousands | Ten thousands | Thousands | Hundreds | Tens | Ones |
| 1 | 3 | 2 | 4 | 6 | 3 | 9 | 4 |
10 ones make 1 ten. 10 tens make 1 hundred. The pattern never stops:
So if the same digit moves one place to the left, it is worth ten times as much. The 4 in 40 is worth 10 times the 4 in 4.
The place value of a digit is the name of its place. The value of a digit is the digit multiplied by its place.
Worked example
In 13 246 394, what are the place value and the value of the digit 2?
Writing a number in expanded form shows the value of every digit:
13 246 394 = 10 000 000 + 3 000 000 + 200 000 + 40 000 + 6 000 + 300 + 90 + 4
In 4 305 100 there is a 0 in the ten thousands place. It tells you there are no ten thousands. Without it the number would become 435 100, which is a much smaller number.
Worked example
Mugisha has the cards 7, 0, 3, 9, 1, 5, 2. What are the biggest and the smallest 7-digit numbers he can make, using every card once?
Tip
Three by three. Start at the right and draw a little line after every three digits. Each group gets its family name: ones, thousands, millions, billions. Now each digit is easy to name.
Work each one in your exercise book first, then tap Show answer to check.
In 58 307 216, which digit is in the ten millions place?
Answer: 5. Counting from the right, the eighth place is ten millions.
What is the value of the digit 7 in 58 307 216?
Answer: 7 is in the thousands place, so its value is 7 × 1 000 = 7 000.
Write 6 040 509 in expanded form.
Answer: 6 000 000 + 40 000 + 500 + 9. The zeros have no value to add, but they keep the other digits in their places.
Using the cards 4, 0, 8, 1, 6, 2, 5 once each, write the biggest and smallest 7-digit numbers.
Answer: Biggest 8 654 210; smallest 1 024 568 (the 0 cannot go first, so it goes second).
How many hundred thousands make one million?
Answer: 10, because each place is worth ten times the place on its right.
What you learned today
Sources and credits
The stories, Rwandan worked examples and practice questions were written by Ganzaa.
Quick check
In 47 182 605, what is the place value of the digit 1?
