Truncate - Definition, Examples, Quiz, FAQ, Trivia
Learn how to truncate numbers with easy explanations, examples, and practice activities
What is Truncation?
Truncation means to cut off a number after a certain place value. It's like using scissors to shorten a number!
When we truncate a number:
- We keep the digits we want
- We remove the digits we don't want
- We don't change the digits that are left
Why do we truncate numbers? Sometimes we need simpler numbers that are easier to work with or understand. Truncation helps us:
- Make big numbers easier to read
- Estimate answers quickly
- Work with approximate values
Key Concept
Truncation is different from rounding because we simply remove extra digits without changing the remaining digits.
How to Truncate Numbers
Truncating numbers is simple when you follow these steps:
Truncation Steps
- Identify the place value where you want to truncate
- Keep all digits to the left of that place
- Remove all digits to the right of that place
- Do not change any of the remaining digits
Truncate to Tens
Original: 347
We keep the hundreds and tens places
Truncate to Tenths
Original: 8.763
We keep the units and tenths places
Truncate to Hundredths
Original: 5.298
We keep up to the hundredths place
Remember
Truncation always makes numbers smaller (or keeps them the same) because we're removing parts without rounding up.
Examples of Truncation
Let's look at more examples of truncation:
Truncation to Different Place Values
| Original Number | Truncated to Tens | Truncated to Units | Truncated to Tenths |
|---|---|---|---|
| 48.73 | 40 | 48 | 48.7 |
| 126.59 | 120 | 126 | 126.5 |
| 3.1416 | 0 | 3 | 3.1 |
| 99.99 | 90 | 99 | 99.9 |
Truncation vs Rounding
| Original Number | Truncated to Tenths | Rounded to Tenths | Difference |
|---|---|---|---|
| 4.78 | 4.7 | 4.8 | 0.1 |
| 3.45 | 3.4 | 3.5 | 0.1 |
| 9.99 | 9.9 | 10.0 | 0.1 |
| 7.21 | 7.2 | 7.2 | 0 |
When to Use Truncation
Truncation is best when you need a quick estimate or when you want to be sure not to overestimate. Rounding is better when you want the closest possible value.
Truncation Practice Quiz
Test your truncation skills with this 5-question quiz. Choose the correct answer for each question.
Frequently Asked Questions
Here are answers to common questions about truncation:
Math Trivia
Discover interesting facts about numbers and truncation:
Ancient Number Systems
The ancient Egyptians used truncation in their measurement systems over 4,000 years ago. They would truncate fractions when building pyramids and monuments.
Computer Calculations
Computers use truncation all the time! When dividing integers, computers truncate the decimal part. For example, 7 ÷ 3 = 2 in computer math.
Pi Truncation
The number pi (π) has been calculated to over 62 trillion digits! But for most calculations, we truncate it to just 3.14 or 3.1416.
Measurement Precision
Scientists sometimes truncate measurements to match the precision of their instruments. If a scale measures to 0.1g, they might truncate 12.34g to 12.3g.
