128.2: Round off the pure repeating (recurring) decimal number to the nearest one (1 whole place)

128.2 rounded to the nearest one (1 whole place) = ?

How is the number rounded off? Half Up, Half Down, Half Away From Zero, Half Towards Zero, Half to Even, Half to Odd. To Ceiling, To Floor.

Rounding a number means replacing it with a simpler, shorter approximation, while keeping its value close to the initial one. The rounded number will be less accurate, but easier to work with.

How is the number rounded off? Explanation.

A repeating decimal has a number of decimals that repeat over and over again, infinitely: 128.2 ≈ 128.222222222222222...


Counting by units (1 whole place at a time), our number is sitting on the axis of numbers between two consecutive neighboring numbers:
128 < 128.2 < 129


Our number is to be rounded off to one of these neighbors, the closer one.


The middle of this interval, the number that is equally close to the either neighbor, is: (128 + 129) ÷ 2 = 128.5


Our number, 128.2 ≈ 128.222222222222222..., is smaller than 128.5, so it is closer to the smaller neighbor: 128


Except for 'To Ceiling, To Floor', the rounded off number (both the positive and the negative) will be equal only to this smaller neighbor.


Rule of thumb:

Rounding digit. Let's call the digit of the position place that is intended to round off to as the 'rounding digit'. The digit is 8: 128.222222222222222...

In a positive number, if the digit to the right of the 'rounding digit' is smaller than 5, then the number is rounded to the smaller neighbor.

The digit is 2: 128.222222222222222... ≈ 128 rounded to the nearest one (1 whole place).


Or, even simpler.
In any number rounded to whole places, if the digit to the right of the 'rounding digit' is less than 5 (0 to 4), then leave the 'rounding digit' as it is and replace all the digits to the right of it with zeros:

128.222222222222222... ≈ 128 rounded to the nearest one (1 whole place)


Below we round off both the positive and the negative:

Half Up, Half Down, Half Away From Zero, Half Towards Zero, Half to Even, Half to Odd. To Ceiling, To Floor.


Number Round Half Up:

Numbers that are halfway between two neighbors are rounded off to the larger neighbor. 128.2 is not halfway between its neighbors.


128.2 ≈ 128


- 128.2 ≈ - 128


rounded to the nearest one (1 whole place)


Number Round Half Down:

Numbers that are halfway between two neighbors are rounded off to the smaller neighbor. 128.2 is not halfway between its neighbors.


128.2 ≈ 128


- 128.2 ≈ - 128


rounded to the nearest one (1 whole place)


Number Round Half Away From Zero:

Numbers that are halfway between two neighbors are rounded off to the neighbor which is farther away from zero. 128.2 is not halfway between its neighbors.


128.2 ≈ 128


- 128.2 ≈ - 128


rounded to the nearest one (1 whole place)


Number Round Half Towards Zero:

Numbers that are halfway between two neighbors are rounded off to the neighbor which is closer towards zero. 128.2 is not halfway between its neighbors.


128.2 ≈ 128


- 128.2 ≈ - 128


rounded to the nearest one (1 whole place)


Number Round Half to Even:
(Gaussian Rounding or Banker's Rounding)

Numbers that are halfway between two neighbors are rounded off to the neighbor with an even rounding digit. 128.2 is not halfway between its neighbors.


128.2 ≈ 128


- 128.2 ≈ - 128


rounded to the nearest one (1 whole place)


Number Round Half to Odd:
(Gaussian Rounding or Banker's Rounding)

Numbers that are halfway between two neighbors are rounded off to the neighbor with an odd rounding digit. 128.2 is not halfway between its neighbors.


128.2 ≈ 128


- 128.2 ≈ - 128


rounded to the nearest one (1 whole place)


Number Round Ceiling:

All the numbers that are between two neighbors are always rounded off to the larger neighbor.


128.2 ≈ 129


- 128.2 ≈ - 128


rounded to the nearest one (1 whole place)


Number Round Floor:

All the numbers that are between two neighbors are always rounded off to the smaller neighbor.


128.2 ≈ 128


- 128.2 ≈ - 129


rounded to the nearest one (1 whole place)


More operations like this:

128.3: Round off the pure repeating (recurring) decimal number to the nearest one (1 whole place)


All Numbers Are Rounded Off: Half Up, Half Down, Half Away From Zero, Half Towards Zero, Half to Even, Half to Odd. To Ceiling, To Floor. Rounding Off Integers, Terminating Decimals, Pure or Mixed Repeating (Recurring) Decimal Numbers

Round off to whole places or decimal places

The latest 13 operations with rounded off numbers:

Round off 128.2 to the nearest one (1 whole place) Apr 18 10:47 UTC (GMT)
Round off 212.55555555555555 to the nearest tenth (1 decimal place) Apr 18 10:46 UTC (GMT)
Round off 0.4 to the nearest one (1 whole place) Apr 18 10:46 UTC (GMT)
Round off 25.2236 to the nearest tenth (1 decimal place) Apr 18 10:46 UTC (GMT)
Round off 1.06798385669987 to the nearest ten (2 whole places) Apr 18 10:46 UTC (GMT)
Round off 335.6 to the nearest one (1 whole place) Apr 18 10:46 UTC (GMT)
Round off 335.6 to the nearest one (1 whole place) Apr 18 10:46 UTC (GMT)
Round off 1.06798385898995 to the nearest ten (2 whole places) Apr 18 10:46 UTC (GMT)
Round off 7.307555675 to the nearest ten (2 whole places) Apr 18 10:46 UTC (GMT)
Round off 276.88889 to the nearest one (1 whole place) Apr 18 10:46 UTC (GMT)
Round off 7.307555675 to the nearest ten (2 whole places) Apr 18 10:46 UTC (GMT)
Round off 7.3075556 to the nearest ten (2 whole places) Apr 18 10:46 UTC (GMT)
Round off 0.0097 to the nearest tenth (1 decimal place) Apr 18 10:46 UTC (GMT)
All the operations with the numbers rounded off by users...

How to round off numbers?

1. Rounding off numbers: definition.

2. How to round off a number to whole places?

3. How to round off a number to decimal places?

4. Mathematical explanation of the rules used in numbers rounding.

5. Special cases. Examples.