Practice with rounding numbers to the nearest tens, hundreds, and thousands

The last post that I posted had to do with place values.  Rounding is kind of like learning the different place values.  In order to round, you need to know what place value you are talking about.  When rounding, you are basically bumping up to a higher number or bumping down to a lower number.  When rounding, you are approximating, meaning you are not finding an exact answer, but an estimate.  There are two things that you need to remember in order to round numbers to the nearest ten.  First, if the number ends in one through four, you need to round down to the next number that ends in zero.  For example, if you need to round 63 to the nearest ten, you will round down to 60.  Second, if the number ends in five or greater, you need to round up to the next even ten.  For example, if you need to round 48 to the nearest ten, you would round up to 50, which is the next even ten.  To round numbers to the nearest hundred is not much different.  For example, round 671 to the nearest hundred.  You must look at the digit right next to the hundreds place, which is 7.  Since it is greater than 5, you will round 671 to 700, versus 600.  Another example: round 825 to nearest hundred.  Since the digit next to the hundreds place is less than 5, you will round 825 down to 800, versus 900.

Lets go back to rounding to the tens place with these two previous examples.  For the first, to round 671 to the nearest tens place, you would look at the digit to the right of the tens place, which is a 1.  Since it is less than 5, you will round 671 down to 670.  For the second, to round 825 to the nearest ten, you would look at the digit to the right of the tens place, which is 5.  Since it is a 5, you will round 825 up to 830.

Now that we have looked at examples of how to round to the nearest tens and hundreds place, lets look at how to round to the nearest hundreds place.  We will go ahead and do a few examples: 1.) Round 4,564 to the nearest thousands place.  Looking at the previous place value, which is the hundreds place, we see a 5, meaning we will round 4,564 down or up?  We will round 4,564 up to 5,000.  2.) Round 7,340 to the nearest thousands place.  Looking at the hundreds place, we see a 3, meaning we will round down.  So, 7,340 rounded to the nearest thousands place is 7,000.  And just so we are on the same page, what would 7,340 rounded to the nearest hundreds place be?  Looking at the previous place value, we see a 4, meaning we will round down, correct?  Correct.  So, 7,340 rounded to the nearest hundreds place would be 7,300.

For further assistance, you can comment on my post, or you can visit the following links to practice and build confidence in yourself =)

http://www.ixl.com/math/grade-4/rounding

http://www.myschoolhouse.com/courses/O/1/16.asp 

http://www.superkids.com/aweb/tools/math/round/round6.cgi and for the answers to this worksheet, go to: http://www.superkids.com/aweb/tools/math/round/round6_answer.cgi