What You Will Learn
After working through this page you will be able to compare any two integers using the symbols <<<, >>>, and ===, and you will know how to arrange a set of integers in ascending or descending order. You will also understand why negative numbers that seem "bigger" (like −100) are actually smaller than those that seem "tiny" (like −1).
Theory
The number line is your best tool
A number line is a straight line where integers are placed in order. Numbers increase as you move to the right and decrease as you move to the left:
⟵−6−5−4−3−2−10123456⟶
Key rule: An integer is greater than any integer to its left and less than any integer to its right.
Comparing two integers
Use the inequality symbols:
| Symbol | Meaning |
|---|---|
| <<< | less than |
| >>> | greater than |
| === | equal to |
Comparing rules at a glance:
- Every positive integer is greater than every negative integer: 1 > −100.
- Every positive integer is greater than zero, and every negative integer is less than zero.
- For two positive integers, the one with the larger absolute value is greater: 8 > 3.
- For two negative integers, the one closer to zero (smaller absolute value) is greater: −2 > −7.
Rule 4 is the one most students find tricky. Think of it this way: −2 is only 2 steps below zero, while −7 is 7 steps below zero, so −2 is higher up on the number line.
Absolute value and comparison
The absolute value of an integer is its distance from zero on the number line:
∣−5∣=5 and ∣5∣=5
Absolute value is always non-negative. It tells you the magnitude, but not the direction. When comparing two negative integers, the one with the smaller absolute value is the greater integer:
∣−3∣=3 and ∣−8∣=8
Since 3 < 8, we know −3 > −8.
Ordering integers
Ascending order (least to greatest) means arranging from leftmost to rightmost on the number line.
Descending order (greatest to least) goes from rightmost to leftmost.
Strategy for ordering a set of integers:
- Separate the numbers into negative, zero, and positive groups.
- Order the negatives: the one with the largest absolute value is the smallest (farthest left).
- Place zero next (if present).
- Order the positives normally.
- Combine the groups.
Example: Order {3,−7,0,−2,5} from least to greatest.
- Negatives (largest absolute value first): −7,−2
- Zero: 0
- Positives: 3,5
- Result: −7,−2,0,3,5
Comparing integers in real-world contexts
Comparing integers is not just abstract math. Consider:
- Temperature: −15°C is colder than −3°C because −15 < −3.
- Elevation: A valley at −50 m is lower than a shore at 0 m because −50 < 0.
- Bank balance: A debt of $200 (−200) is worse than a debt of $50 (−50) because −200 < −50.
Worked Examples
Example 1: Comparing two negative integers (easy)
Problem: Insert <<<, >>>, or === between −4 and −9.
Step 1: Find the absolute values. ∣−4∣=4 and ∣−9∣=9.
Step 2: Both are negative. The one with the smaller absolute value is greater. 4 < 9 ⟹ −4 > −9.
Answer: −4 > −9.
Example 2: Comparing a negative and a positive integer (easy)
Problem: Insert <<<, >>>, or === between −12 and 3.
Step 1: One is negative and the other is positive. Every positive integer is greater than every negative integer.
Answer: −12 < 3.
Example 3: Ordering five integers in ascending order (medium)
Problem: Arrange 8,−3,−11,0,5 from least to greatest.
Step 1: Identify the negatives, zero, and positives.
- Negatives: −11,−3
- Zero: 0
- Positives: 5
Step 2: Order the negatives (largest absolute value = smallest value). −11 < −3.
Step 3: Combine all groups.
Answer: −11,−3,0,5.
Example 4: Ordering with duplicates in descending order (medium)
Problem: Arrange −5,2,−5,7,0,−1 from greatest to least.
Step 1: In ascending order first: −5,−5,−1,0,2,7.
Step 2: Reverse for descending order.
Answer: 7,2,0,−1,−5,−5.
Example 5: Real-world comparison (challenging)
Problem: During a science experiment, rank the sensors from coldest to warmest: Sensor A: −8°C, Sensor B: −3°C, Sensor C: 2°C, Sensor D: −8°C.
Step 1: Order the temperatures from least to greatest. −8 < −8 < −3 < 2.
Step 2: Map back to sensors.
- Coldest (tied): Sensor A and Sensor D (both −8°C)
- Next: Sensor B (−3°C)
- Warmest: Sensor C (2°C)
Answer: Coldest to warmest: A = D, B, C.
Common Mistakes
Mistake 1: Thinking a "bigger" negative number is greater.
✅ −10 < −2.
Mistake 2: Confusing the direction of <<< and >>>. ✅ 5 > 3.
Mistake 3: Forgetting zero when ordering.
✅ −4,−1,0,3,7.
Practice Problems
- Insert <<<, >>>, or ===: −6 □ −1.
- Insert <<<, >>>, or ===: −15 □ 0.
- Order from least to greatest: 4,−9,1,−3,0,−9.
- Order from greatest to least: −20,15,−7,0,8,−20.
- Coldest and warmest temperature during a week.
Solutions: 1. −6 < −1
2. −15 < 0
3. −9,−9,−3,0,1,4
4. 15,8,0,−7,−20
5. Coldest: −5°C, Warmest: 3°C.
Summary
- On a number line, numbers increase to the right and decrease to the left.
- Every positive integer is greater than every negative integer, and both are compared to zero.
- For two negative integers, the one closer to zero is greater: −2 > −7.
- Ascending order = least to greatest.
- Descending order = greatest to least.