Rounding to the Nearest 10 and 100
To round a number to the nearest ten, find the two tens it sits between and choose the closer one: 347 lies between 340 and 350, so it rounds to 350. Rounding to the nearest hundred works the same way with hundreds, and 347 rounds to 300.
Rounding on a number line
Draw a short number line from the ten below to the ten above. For 347 that is 340 to 350, with the halfway point 345 in the middle. 347 is past the halfway point, closer to 350, so it rounds up to 350.
To round to the nearest hundred, the number line runs from 300 to 400 and the halfway point is 350. 347 is just before 350, so it rounds down to 300. The same number can round up to the nearest ten and down to the nearest hundred.
The rounding rule: 5 or more, round up
- Find the rounding place: the tens digit when you round to the nearest 10, the hundreds digit when you round to the nearest 100.
- Look at the digit just to its right. Only this digit decides.
- If it is 0, 1, 2, 3 or 4, keep the rounding digit (round down).
- If it is 5, 6, 7, 8 or 9, add 1 to the rounding digit (round up).
- Write zeros in all places to the right of the rounding place.
Round 35 to the nearest ten
- 35 lies between 30 and 40, exactly halfway.
- The ones digit is 5, and 5 rounds up.
Answer: 40
Round 95 to the nearest ten
- 95 lies between 90 and 100.
- The ones digit is 5, so round up: 9 tens + 1 ten = 10 tens, which is 100.
Answer: 100
Rounding 3-digit numbers to the nearest hundred
When rounding to the nearest hundred, the tens digit decides and the ones digit does not matter at all. Covering the ones digit with a finger helps children look at the right place.
Round 449 to the nearest hundred
- 449 lies between 400 and 500; the halfway point is 450.
- The tens digit is 4, less than 5, so round down. The 9 ones do not count.
Answer: 400
Round 862 to the nearest ten and to the nearest hundred
- Nearest ten: the ones digit is 2, so round down to 860.
- Nearest hundred: the tens digit is 6, so round up to 900.
Answer: 860 and 900
Rounding is a quick way to check sums: 298 + 412 is about 300 + 400 = 700, so the exact answer, 710, looks right.
Examples
Round 347 to the nearest hundred
Round 562 to the nearest hundred
Practice problems with answers
Solve these problems on paper or out loud, then check the answer key. The online practice and the printable worksheet give a new set every time.
- Round 606 to nearest hundred
- Round 658 to nearest hundred
- Round 273 to nearest hundred
- Round 223 to nearest hundred
- Round 213 to nearest hundred
- Round 319 to nearest hundred
- Round 257 to nearest hundred
- Round 888 to nearest hundred
Show answers
- 600
- 700
- 300
- 200
- 200
- 300
- 300
- 900
Common mistakes
- Looking at the wrong digit: to round 449 to the nearest hundred, only the tens digit counts, so the answer is 400, not 500.
- Rounding in two steps: 449 → 450 → 500. Always round the original number in one step.
- Rounding 5 down: 35 rounds to 40, and 250 rounds to 300 when you round to the nearest hundred.
- Getting stuck when the digit to round is 9: 95 rounds up to 100, and 962 rounds to 1,000 when rounding to the nearest hundred.
Questions parents ask
How do you round to the nearest ten?
Look at the ones digit. If it is 0 to 4, keep the tens and write 0 in the ones place (63 → 60). If it is 5 to 9, go up to the next ten (67 → 70).
Does 5 round up or down?
In school math, 5 always rounds up: 35 rounds to 40 and 650 rounds to 700. A number like 35 sits exactly halfway on the number line, so we need a rule, and the rule is "5 or more, round up".
What is 449 rounded to the nearest hundred?
400. The tens digit is 4, so it rounds down. Rounding to 450 first and then to 500 is a common mistake.
In which grade do kids learn rounding?
Rounding to the nearest 10 and 100 is a 3rd grade Common Core standard (3.NBT.A.1). In 4th grade children round larger numbers to any place.