Understanding Decimal Place Value

The almighty decimal point. Who would have thought that one little period could mean so much? Understanding its importance and how it affects place value really isn't too complicated. If, by chance, you need a refresher course so you can help your children with their homework, here is what you will need to know.

Instructions

1. What is the purpose of the decimal point? The decimal point has an important job, not only in mathematical matters, but in money matters as well. It determines the value of the digits in a set of numbers.

2. What is place value? Numbers are considered digits. They each have a value, depending on where they are located. In the number 123, the 1 represents the amount of hundreds, the 2 represents the amount of tens, and the 3 represents the amount of ones.

3. How does the decimal point change this? If you add a decimal point to 123, it would look like this: 1.23. This gives the numbers an entirely different value. The 1 is no longer considered a hundred, but is now representing the amount of ones there are. The 2 to the right of the decimal now represents the tenths in the number and the 3 is now considered to be in the hundredths position. However, neither the 2 or the 3 have a full value. They are a fraction of what they were before the decimal was added.

4. Why is the placement of the decimal so important? If you have recorded that you have $100.00 in your checking account and in actuality only have $10.00, it is most likely because you placed the decimal point too far to the right by only a single digit. Yet that one digit made a huge difference in the funds that you thought were available. This is because the placement of the decimal point determined the value of the individual digits.