Thousands to Trillions
Once you have mastered ones, tens and hundreds, the number system extends outward in a predictable pattern. Every group of three places forms a period, and each new period is given a name: thousands, millions, billions and beyond.
The Place Value Periods
| Period | Places Included | Starts at |
|---|---|---|
| Ones | Ones, Tens, Hundreds | 1 |
| Thousands | Thousands, Ten Thousands, Hundred Thousands | 1,000 |
| Millions | Millions, Ten Millions, Hundred Millions | 1,000,000 |
| Billions | Billions, Ten Billions, Hundred Billions | 1,000,000,000 |
| Trillions | Trillions, Ten Trillions, Hundred Trillions | 1,000,000,000,000 |
Full Place Value Chart
| Place | Value | Digits in Number |
|---|---|---|
| Ones | 1 | 1-digit |
| Tens | 10 | 2-digit |
| Hundreds | 100 | 3-digit |
| Thousands | 1,000 | 4-digit |
| Ten Thousands | 10,000 | 5-digit |
| Hundred Thousands | 100,000 | 6-digit |
| Millions | 1,000,000 | 7-digit |
| Ten Millions | 10,000,000 | 8-digit |
| Hundred Millions | 100,000,000 | 9-digit |
| Billions | 1,000,000,000 | 10-digit |
| Trillions | 1,000,000,000,000 | 13-digit |
Reading a Large Number
Consider 4,725,038,196. Break it into periods from right to left:
4 | 725 | 038 | 196 → Four billion, seven hundred twenty-five million, thirty-eight thousand, one hundred ninety-six
How Each Period Relates to the Previous
| Relationship | Value |
|---|---|
| 1 thousand = 10 hundreds | 1,000 |
| 1 million = 1,000 thousands | 1,000,000 |
| 1 billion = 1,000 millions | 1,000,000,000 |
| 1 trillion = 1,000 billions | 1,000,000,000,000 |
Real-World Scale
- A typical school has a few hundred students.
- A large city may have a few million residents.
- The world population is about 8 billion people.
- The US national debt is measured in trillions of dollars.
- The distance to the nearest star in kilometres runs into the trillions.
Key Points
- Places are grouped into periods of three: ones, thousands, millions, billions, trillions.
- Each period is 1,000 times greater than the previous period.
- Commas separate periods and make large numbers easy to read.
- The pattern of ones, tens, hundreds repeats inside every period.
Quick Practice
- Write 6 million, 300 thousand, 45 as a numeral.
- What is the place value of 9 in 9,204,761?
- How many millions are in one billion?
- Write 12,005,000,000 in words.
- What period contains the digit 7 in 47,832,000?
Summary
The decimal number system extends far beyond hundreds by grouping places into periods. Each period – thousands, millions, billions, trillions – is one thousand times larger than the period before it. Once you understand the ones period, you can read and write numbers of any size by applying the same pattern.