Rounding Decimal Numbers Part 1

Recall the place value chart. The number 12.35 can be written in the place value chart as follows:

 

Ones	Tens	.	Tenths	Hundredths
1	2	.	3	5

 

Steps for rounding decimals:

 

To round the decimal number to a given place, locate the rounding digit (which is the digit at the place you are rounding to). Then, check the digit immediately to its right.

 

• If this digit is 5 or more, then add 1 to the rounding digit (this is called rounding up) and remove all the digits to its right.
   
• If this digit is less than 5, then keep the rounding digit the same (this is called rounding down) and remove all the digits to its right.

 

 

For example: To round the number 70.17 to the nearest tenths, look at its hundredths place digit.

It is 7, which is greater than 5. So, we round up.

 

70.17 → 70.2

 

So, 70.17 rounded to the nearest tenth is 70.2.