Rounding Numbers
Rounding makes numbers simpler by finding the nearest 10, 100, or 1000. We use rounding for estimates and when exact answers are not needed.
What You Need to Know
Key Concept Diagram
Look at the digit after the place you are rounding to
If it is 5 or more, round up; if it is 4 or less, round down
Rounding to the nearest 10 looks at the ones digit
Rounding to the nearest 100 looks at the tens digit
Key Vocabulary
Round
Replace a number with a nearby value that is simpler or easier to work with
Estimate
An approximate answer found by rounding or using mental maths
Nearest 10
The multiple of 10 closest to the given number
Nearest 100
The multiple of 100 closest to the given number
Knowledge Check
Select the correct answer for each question. Click "Check Answer" to see if you are right.
Question 1
Round 347 to the nearest 10.
Question 2
Round 2,463 to the nearest 100.
Question 3
A crowd of 3,748 people attended. Rounded to the nearest 1000, about how many attended?
Key Concepts Summary
- ●Look at the digit after the place you are rounding to
- ●If it is 5 or more, round up; if it is 4 or less, round down
- ●Rounding to the nearest 10 looks at the ones digit
- ●Rounding to the nearest 100 looks at the tens digit