Comprehensive Calculator Guide
This calculator rounds any number to the nearest thousand, hundred, ten, whole number or one to three decimal places by the school rule, showing the deciding digit and the difference. 3.14159 to two places is 3.14, 4567 to the nearest thousand is 5000, and 2.5 to the nearest whole number is 3.
The rule
Look at the digit just right of the place: 5 or more rounds up, under 5 leaves it. Some software rounds half to even (2.5 → 2) to avoid bias. This calculator rounds on the decimal digits as written, so 1.005 to two places is 1.01.
How to Use
- Enter the number.
- Choose the place.
- Press “Round” to see the result, the deciding digit and the difference.
Formula Used
5 or more rounds up; under 5 stays
Practical Examples
- Example 1
- 3.14159 → 3.14.
- Example 2
- 4567 → 5000.
- Example 3
- 2.5 → 3.
Important Tips
- Look at one digit only.
- Round at the end.
- Money: two decimal places.
Common Mistakes to Avoid
- Rounding in stages: 4.45 → 4.5 → 5.
- Looking at the wrong digit.
- Dropping zeros: 4567 → 5000, not 5.
Frequently Asked Questions
- How do I round to the nearest ten?
- Look at the ones digit: 47 → 50.
- What is 2.5 rounded?
- 3 at school, 2 with round-half-to-even.
- Rounding vs truncating?
- 3.79 truncates to 3.7, rounds to 3.8.