Compare and Order Decimals Less Than One

6N3.2

Get ready!• Look at the table

• Which city has the longest subway system? Explain

Compare and order decimals

•Comparing decimals is similar to comparing whole numbers. You can use the symbols > or < to indicate that one quantity is greater than or less than the other.

• Decimals that name the same number are called equivalent decimals.• Examples are 0.8 and 0.80 equivalent means same

Equivalent decimals

•When you add zeros to the right of the last digit in a decimal, the value of the decimal does not change. Adding zeros is useful when ordering a group of decimals.

Remember:

Which number is greater?

Compare 0.3 and 0.25

Rule for comparing: Always start and the left and move right – compare values of digits as you move.

Compare 0.3 and 0.25

• Step 1: Start at the number on the left – in this case 0 • Both digits are equal

• Step 2: Move to the next place value (tenths)• The digits are different

• 3 > 5

• Therefore, 0.3 > 0.25

Compare 0.217 and 0.271

•Step 1: Start at the place value on the left – in this case it’s 0• Both digits are equal

•Step 2: Move to the next place value – both digits are 2 (equal)•Step 3: Move to the next place value – the digits are different• 7 > 1

•Therefore, 0.271 > 0.217

You try it!

Compare the decimals. Write >, <, or =1) 0.345 0.3542) 47.58 45.783) 13.344 13.4334) 583.583 583.5835) 565.659 565.656

Order Decimals

• Ordering decimals follows the same rules as ordering whole numbers• Line up the digits and the decimal point and compare

the numbers

Example

•Order 0.91 0.9 0.87•Line up the decimals

0.910.900.87

•Uh-oh! I have an open place value!•No problem! Just put a 0 there to fill its place --- it DOES NOT change the value of the decimal.

Example 1 continued…

• Compare the numbers0.910.900.87

0.87 is the least, then 0.90, and 0.91 is the greatest

Example 2

•Order 0.057 0.781 0.08•Line up the decimals

0.0570.7810.080

•Uh-oh! I have an open place value!•No problem! Just put a 0 there to fill its place --- it DOES NOT change the value of the decimal.

Example 2 continued…

• Compare the numbers 0.057 0.781 0.080

0.057 is the least, then 0.080, and 0.781 is the greatest

You try it!

Order each set from least to greatest

1) 0.547 0.541 0.52) 0.81 0.589 0.8173) 0.41 0.83 0.58

• Order 15, 14.95, 15.8 and 15.01 from least to greatest.

• The order from least to greatest is 14.95, 15, 15.01 and 15.8

Example:

• Use >, <, or = to compare each pair of decimals

• 0.4 □ 0.5

• 2.7 □ 2.07

• 0.38 □ 0.35

• 25.5 □ 25.50

Check your understanding!

Practice

Order each set of decimals from least to greatest.