Rounding decimals

When rounding decimals, follow the three steps below:

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.


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

Other examples:

Round 5.18 to tenths

The answer is 5.2

Round 0.498 to hundredths

The answer is 0.50

Note that adding 1 to 9 gives 10. Write down 0 and put the 1 above 4; Finally add 1 to 4 to get 5. 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.