Rounding decimals

When rounding decimals, follow the three steps outlined below to the letter. Do you struggle to understand the steps outlined below? Do you need more explanations? Check the figure at the end of this lesson.

Here are the steps to follow when rounding decimals 


Step #1:

Find the place you are rounding to. Is it the tenths, the hundredths, or the thousandths?

Step #2:

If the digit to the right of the place you are rounding to is 5 or more, add 1 to the place you are rounding to. If it is less than 5, add nothing.

Step #3: Drop all the digits to the right of the place you are rounding to.

A couple of examples showing how to round decimals by following the steps outlined above.


Example #1: Round 2.1582 to hundredths.

Step #1

The place you are rounding to is the place the number 5 holds: 2.1582

Step #2

The digit to the right of 5 is 8 and it is at least 5.

Therefore, we can add 1 to 5 to make it 6.

Step #3

Drop 82 (all digits to the right of 5)

The answer is 2.16

Example #2: Round 4.241 to tenths

Step #1

The place you are rounding to is the place the number 2 holds: 4.241

Step #2

The digit to the right of 2 is 4 and it is less than 5.

Therefore, we add nothing to 2.

Step #3

Drop 41 (all digits to the right of 2)

The answer is 4.2

A few more examples showing how to round decimals

Round 5.18 to tenths

1 is in the tenths place. Since 8 ≥ 5, add 1 to 1 and the answer is 5.2.

Round 0.498 to hundredths

9 is in the hundredths place. Since 8 ≥ 5, add 1 to 9 and the answer is 0.50.

Note that adding 1 to 9 gives 10. Write down 0 in the hundredths place and carry the 1 to the tenths place. Just put the 1 above the 4; Finally add 1 to 4 to get 5. If you are having a hard time understanding this, just go to adding decimals for more information.

Round 0.04 to tenths

The answer is 0.0

Note that we do not add anything to 0 because 4 is less than 5.

This figure summarizes the steps to round decimals

Rounding decimals

Rounding decimals quiz. Use the quiz below to test your knowledge.