Compare decimal numbers
key notes :
Comparing decimals means determining which decimal represents a larger number, and which represents a smaller number.
Ordering decimals means putting them in order from the least to the greatest, or from the greatest to the least.
| = | When two values are equal, we use the “equals” sign | example: 0.2+0.2 = 0.4 |
|---|---|---|
| < | When one value is smaller than another, we can use a “less than” sign. | example: 0.3 < 0.5 |
| > | When one value is bigger than another, we can use a “greater than” sign | example: 0.9 > 0.6 |
How to Tell Which Decimal is Bigger
When given two decimal numbers, how can someone tell which decimal is bigger? The process is similar to what is done when words are alphabetized. If the first letter of each word is the same, look at the second letter. If the second letter is the same, look at the third letter. Here is how to tell which decimal number is bigger:
- Write the numbers with the decimal points lined up.
- Starting at the far left, which is the largest place value, compare the numbers.
- If the first-place value is the same in both numbers, move one spot to the right and compare again.
- If the second place value is the same in both numbers, move one spot to the right and compare again.
- Continue until the place value digits are different. The number with the larger digit is the larger number.
Here is an example.
Learn with an example
Which number is bigger, 8.019 or 8.03?
Follow the steps:
- Write the numbers with the decimal points lined up.
| 8 | . | 0 | 1 | 9 |
| 8 | . | 0 | 3 |
- Starting at the far left, which is the largest place value, compare the numbers.
The digit in the ones place in both numbers is an 8.
- If the first-place value is the same in both numbers, move one spot to the right and compare again.
The digit in the tenths place in both numbers is a 0.
- If the second place value is the same in both numbers, move one spot to the right and compare again.
The digit in the hundredths place in the top number is a 1, and it is a 3 in the bottom number.
- The number with the larger digit is the larger number.
Since 3 is bigger than 1, then 8.03 > 8.019
8.03 > 8.019
Which decimal is less than the one shown in this diagram?
- 0.46
- 0.37
- 0.5
- 0.43
Write the decimal shown.
There are 10 columns. There are 4 coloured columns. The decimal part is four tenths.
Write four tenths as a decimal: 0.4.
The decimal shown is 0.4. Look for the decimal that is less than 0.4.
0.37 is less than 0.4. Remember that 0.4 is equivalent to 0.40. The tenths digit in 0.37 is less than the tenths digit in 0.40.
Which decimal is greater than the one shown in this diagram?
- 0.13
- 0.15
- 0.0
- 0.1
Write the decimal shown.
There are 100 squares. There are 14 coloured squares. The decimal part is fourteen hundredths.
Write fourteen hundredths as a decimal: 0.14.
The decimal shown is 0.14. Look for the decimal that is greater than 0.14.
0.15 is greater than 0.14. The hundredths digit in 0.15 is greater than the hundredths digit in 0.14.
Let’s practice!
