Answer: Rounding Whole Numbers
Step-by-step explanation: There are many times in real life where numbers need to be made easier so that they can be quickly added or subtracted mentally. Adding or subtracting whole numbers is hard when the numbers are not simple. There is a lot of opportunity to make a mistake. It's easier to add 50 and 60 mentally than it is to add 54 and 67. Rounding helps to reduce the chance of making a mistake. So, what exactly is rounding whole numbers?
First, a whole number is any number that does not contain a decimal or a fraction and is positive. Basically, if it can be counted to, it's a whole number. Rounding is making a number simpler by changing it to the closest place value. Rounding whole numbers are all based on the place values of whole numbers. A good way to think about rounding as a concept is to think about the word around it. If your mom is somewhere on your property, but she doesn't say where an answer to where she is would be that she is around. Around is less specific than, she's in the kitchen, just like 50 is simpler and less specific than 57.
Before getting into the rules or processes of rounding, place value needs to be reviewed. Let's assume the whole number is 3593. There are 4 digits in this number and each one is in a specific place value column.
Ones - The ones place is the furthest digit to the right of a whole number. 3 is in the one's place.
Tens - The tens place is one digit to the left of the one's place and represents a group of 10 ones. The 9 is in the tens place.
Hundreds - The hundreds place is direct to the left of the tens and the 3rd digit from the left of the number. It represents a group of 100 ones or 10 tens. The 5 is in the hundreds place.
Thousands - The thousands place is the digit to the left of the hundreds and the 4th digit from the left. It represents a group of 1000 ones, 100 tens, and 10 hundred. The 3 is in the thousands place.
The process of rounding begins by focusing on place value. When a number is rounded, the very thing that must be known is which place value the number is being rounded to. In real life, the answer will depend on how accurate the numbers need to be. In a math problem, the place value to be rounded will be part of the question. It will say something like round to the nearest or round by.
Rounding is a step-by-step process. The following steps will outline the process of rounding whole numbers. For the steps, the number 473 will be used as an example.
Determine what place value the number is being rounded by. (The number will be rounded by tens)
Locate the place value and identify the digit in the column. (7 is in the tens place)
Move to the place value directly to the right of the place value being rounded by (Directly to the right of the tens is the ones. The digit in the ones is 3.)
If the digit is 1, 2, 3, or 4 then the number will be rounded down. If the digit is 5, 6, 7, 8, or 9 the number will be rounded up. (The digit is 3, so the number will be rounded down.)
If the number needs to be rounded down, then the digit in the place that is being rounded stays the same. If the number needs to be rounded up, the digit will increase by 1. (The digit in the ten is 7, so it will either stay at 7 or change to 8. The digit stays at 7 in the example.)
Change all the digits in the place values to the right of the place value being rounded by 0. (The number is rounded by tens, so the one digit changes to zero.)
The digits in the place values to the left of the place value being rounded will remain the same. (4 is in the hundreds place and stays the same.)
The result is then written down. (473 rounded by tens is 470)
If the steps are followed in the right order, rounding is a fairly simple task. There are some tips and rules that are important to note.