Rounding decimals

It is important to have an understanding of place value before we can begin to round decimals. The decimal point is placed between the units column and the tenths column.

Below is a chart illustrating place value in the decimal system.

Table shows place value from millions to millionths and shows the position of 125.2408.

Detailed description of diagram.

We can round off to any given number of decimal places:

1 decimal place (tenths)
2 decimal places (hundredths)
3 decimal places (thousandths)
4 decimal places (ten-thousandths)
whole numbers.

The use of a number line may assist us in making decisions with rounding decimals.

We can establish where the decimal number lies on the number line.

Rounding using rules

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