Math Background

Comparing and Ordering Integers and Decimals: When Students Ask

  • Why should I learn this?
    Students no doubt can name situations in which they order and compare whole numbers. Students should also realize that many situations require them to compare and order numbers in decimal form. These include times when they are dealing with money amounts, metric measurements, calculator sums, and sports records. Using decimals may be somewhat foreign to students at this age. Explain that an understanding of decimals will help prepare them for algebra. Most students are excited about the idea of learning algebra. They may see it as a transition from “little kid” math to “grown-up” math. A good understanding of integers is an important factor in a student's ability to learn algebra.
  • How do I compare whole numbers and decimals?
    One way you can compare whole numbers and decimals is to use a number line. On a number line, the lesser number is to the left of the greater number. Remember, left is lesser. You can also compare place values. Write one number under the other, lining up the place values—ones under ones, tenths under tenths, and so on. Compare the digits, beginning with the greatest place-value position, left to right. When you find digits that differ in value, the number with the greater digit is the greater number.
  • How can I remember the place names for decimals?
    You may want to have students make a decimal place-value model to tape to their desks for reference. Help students to see the correlation between the names: tens/tenths, hundreds/hundredths, thousands/thousandths, and so on. A ten has one zero; the tenths place is one place to the right of the decimal point. One hundred has two zeros; the hundredths place is two places to the right of the decimal point. One thousand has three zeros; the thousandths place is three places to the right of the zero, and so on.

Houghton Mifflin Math Grade 5