Comparing and Ordering Numbers
Learning Objectives
- Use <, >, and = symbols correctly
- Order sets of numbers from least to greatest and greatest to least
Concept Explanation
Comparing numbers means determining which number is greater than, less than, or equal to another number. We use the symbols > (greater than), < (less than), and = (equal to) to show these relationships. When comparing multi-digit numbers, we start by comparing the digits in the highest place value position.
Ordering numbers involves arranging them in sequence, either from smallest to largest (ascending order) or largest to smallest (descending order).
Worked Examples
Example 1
Problem: Compare 45 and 54 using the correct symbol.
Solution: 45 < 54
Explanation: Both numbers have the same digits, but in 54, the 5 is in the tens place, making it larger than 45.
Example 2
Problem: Order these numbers from least to greatest: 37, 73, 33, 77
Solution: 33, 37, 73, 77
Explanation: Compare the tens place first, then the ones place to determine the order.
Example 3
Problem: Which symbol makes this statement true? 82 ___ 28
Solution: 82 > 28
Explanation: 82 has 8 tens and 2 ones, while 28 has 2 tens and 8 ones. Since 8 tens is more than 2 tens, 82 is greater than 28.
Common Errors
Error | Correction | Reason |
---|---|---|
Confusing the < and > symbols | Remember the symbol points to the smaller number | The wide part of the symbol faces the larger number. |
Comparing only the first digit | Compare digits in the same place value | 25 is not greater than 19 just because 2 > 1; compare tens to tens. |
Ignoring place value | Start comparing from the highest place value | When comparing 352 and 348, look at the hundreds first (3=3), then tens (5>4). |
Practice Problems
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Problem: Compare 67 and 76 using the correct symbol.Solution: 67 < 76
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Problem: Order from greatest to least: 15, 51, 55, 11Solution: 55, 51, 15, 11
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Problem: Which symbol makes this true? 43 ___ 34Solution: 43 > 34
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Problem: Order from least to greatest: 102, 120, 210, 201Solution: 102, 120, 201, 210
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Problem: Compare 199 and 201 using the correct symbol.Solution: 199 < 201
Real-World Application Example
Comparing and ordering numbers is essential for many everyday activities, such as finding the best price when shopping, determining which team scored more points in a game, or organizing data in a meaningful way. These skills help us make informed decisions based on numerical information.
Related Concepts
- Rounding Numbers (Number Sense & Place Value)
- Understanding Place Value (Number Sense & Place Value)
- Writing Numbers in Expanded Form (Number Sense & Place Value)