Subtraction Facts Within 20 - Grade 2 Mathematics - Exercises with solutions

Master subtraction facts within 20: basic subtraction, number bonds, counting back, fact families, and subtraction strategies through these 10 detailed exercises with verified solutions.

Solutions: Exercises 1 to 10
1 Basic subtraction
Exercise 1
What is 15 - 7?
Difficulty: Beginner Time: ~2 minutes Skills: Basic Subtraction Within 20
Definition:

Subtraction within 20: Taking away one number from another where the result is also within the range of 0 to 20

Note: Subtraction within 20 builds foundational skills for more complex arithmetic.

Step-by-step subtraction method:
  1. Start with the first number (minuend)
  2. Take away the second number (subtrahend)
  3. Count how many are left (difference)
Original Problem
15 - 7
Solution
8
Step 1: Start with 15

We have 15 objects: ⭐⭐⭐⭐⭐⭐⭐⭐⭐⭐⭐⭐⭐⭐⭐

Step 2: Take away 7

Remove 7 objects: ⭐⭐⭐⭐⭐⭐⭐ (⭐⭐⭐⭐⭐⭐⭐)

Step 3: Count what's left

8 objects remain: ⭐⭐⭐⭐⭐⭐⭐⭐

15 - 7 = 8
Final answer:

15 - 7 = 8

Applied rules:

• Subtraction: Take away the subtrahend from the minuend

• Counting: Count how many remain after taking away

• Within 20: Both operands and result are ≤ 20

Related Examples:
  • 14 - 6 = 8 - Practice with different combinations
  • 18 - 9 = 9 - Practice with doubles facts
  • 13 - 5 = 8 - Practice with smaller differences
Quick Tips:
  • Subtraction is the opposite of addition
  • You can check by adding: 8 + 7 = 15 ✓
  • Always start with the bigger number when subtracting
Frequently Asked Questions:

Q: What does "within 20" mean?
A: All numbers in the problem (minuend, subtrahend, and difference) are 20 or less.

Q: How do I know if I'm doing subtraction within 20?
A: Check that the first number is 20 or less and the result is also 20 or less.

2 Number bonds
Exercise 2
What is 16 - 9?
Difficulty: Beginner Time: ~2 minutes Skills: Number Bonds, Part-Whole Relationships
Definition:

Number bond: Shows how numbers are related in addition and subtraction within 20

Note: Number bonds help us understand that 16 can be broken into 9 and 7.

Step-by-step number bond method:
  1. Think about what number goes with 9 to make 16
  2. Use the relationship: 9 + ? = 16
  3. Since 9 + 7 = 16, then 16 - 9 = 7
Original Problem
16 - 9
Number Bond
9 + 7 = 16
Solution
7
Step 1: Think about the whole

We want to break apart 16

Step 2: One part is 9

So 16 = 9 + ?

Step 3: Find the missing part

9 + 7 = 16, so 16 - 9 = 7

16 - 9 = 7
Final answer:

16 - 9 = 7

Applied rules:

• Number bond: 16 can be split into 9 and 7

• Relationship: Addition and subtraction are inverse operations

• Within 20: All numbers in the problem are ≤ 20

Related Examples:
  • 15 = 8 + 7, so 15 - 8 = 7
  • 18 = 9 + 9, so 18 - 9 = 9
  • 14 = 6 + 8, so 14 - 6 = 8
Quick Tips:
  • Number bonds help you see subtraction as "what's missing?"
  • Know your number bonds to 20: pairs that add up to 11, 12, ..., 20
  • Use addition to check: 7 + 9 = 16 ✓
Frequently Asked Questions:

Q: What are number bonds within 20?
A: Number bonds that involve numbers 0-20, showing how a number can be split into parts.

Q: How do number bonds help with subtraction within 20?
A: They help you think "what number added to 9 gives me 16?" which leads to 16 - 9 = 7.

3 Counting back strategy
Exercise 3
What is 18 - 5?
Difficulty: Beginner Time: ~2 minutes Skills: Counting Back Strategy
Definition:

Counting back: Starting from the first number and counting backwards by the second number within 20

Note: This is a mental math strategy for subtraction within 20.

Step-by-step counting back method:
  1. Start at the first number (18)
  2. Count backwards by the second number (5)
  3. Land on the answer (13)
Original Problem
18 - 5
Counting Back
18 → 17 → 16 → 15 → 14 → 13
Solution
13
Step 1: Start at 18

Begin counting: 18

Step 2: Count back 5

18 → 17 → 16 → 15 → 14 → 13 (count 5 steps back)

Step 3: Land on the answer

We land on 13

18 - 5 = 13
Final answer:

18 - 5 = 13

Applied rules:

• Counting back: Move backwards on the number line

• Strategy: This helps with mental math

• Within 20: All numbers in the problem are ≤ 20

Related Examples:
  • 17 - 4: Start at 17, count back 4 → 17, 16, 15, 14, 13 → Answer: 13
  • 15 - 3: Start at 15, count back 3 → 15, 14, 13, 12 → Answer: 12
  • 20 - 6: Start at 20, count back 6 → 20, 19, 18, 17, 16, 15, 14 → Answer: 14
Quick Tips:
  • Count back slowly and carefully
  • This strategy works best for small numbers being subtracted
  • Use your fingers to help keep track of counting back
Frequently Asked Questions:

Q: When should I use counting back within 20?
A: Use it for small subtrahends (like subtracting 1, 2, 3, 4, or 5).

Q: What if I count back too far?
A: Start over and count more carefully, or use objects to help.

Solutions: Exercises 4 to 5
4 Fact families
Exercise 4
If 7 + 5 = 12, what is 12 - 5?
Definition:

Fact family: A group of related addition and subtraction facts using the same numbers within 20

Note: The numbers 7, 5, and 12 form a fact family: 7+5=12, 5+7=12, 12-5=7, 12-7=5.

Step-by-step fact family method:
  1. Recognize that 7, 5, and 12 are in the same fact family
  2. If 7 + 5 = 12, then 12 - 5 = 7 (the other addend)
  3. Verify: 7 + 5 = 12 and 12 - 5 = 7
Given Fact
7 + 5 = 12
Related Subtraction
12 - 5 = ?
Solution
7
Step 1: Recognize the fact family

Numbers 7, 5, and 12 are related

Step 2: Use the relationship

If 7 + 5 = 12, then 12 - 5 = 7

Step 3: Verify the answer

7 + 5 = 12 ✓ and 12 - 5 = 7 ✓

12 - 5 = 7
Final answer:

12 - 5 = 7

Applied rules:

• Fact family: Addition and subtraction facts using same numbers

• Inverse operations: Addition and subtraction undo each other

• Within 20: All numbers in the fact family are ≤ 20

Related Examples:
  • If 6 + 8 = 14, then 14 - 8 = 6
  • If 9 + 4 = 13, then 13 - 4 = 9
  • If 8 + 7 = 15, then 15 - 7 = 8
Quick Tips:
  • Fact families show the connection between addition and subtraction
  • Knowing one fact helps you know three others
  • Use fact families to check your work
Frequently Asked Questions:

Q: What is a fact family within 20?
A: A group of related addition and subtraction facts using the same three numbers, all ≤ 20.

Q: How do fact families help with subtraction within 20?
A: If you know an addition fact, you automatically know the related subtraction facts.

5 Missing numbers
Exercise 5
What number makes this sentence true: 16 - ? = 9?
Definition:

Missing number: Finding the unknown value in a subtraction equation within 20

Note: We need to find what number subtracted from 16 gives 9.

Step-by-step missing number method:
  1. Think: "What number taken from 16 leaves 9?"
  2. Use addition: 9 + ? = 16
  3. Since 9 + 7 = 16, then 16 - 7 = 9
Original Problem
16 - ? = 9
Inverse Operation
9 + ? = 16
Solution
7
Step 1: Understand the problem

We need to find what number subtracted from 16 equals 9

Step 2: Use inverse operation

Instead of subtracting, we add: 9 + ? = 16

Step 3: Solve the addition

9 + 7 = 16, so the missing number is 7

Step 4: Verify

16 - 7 = 9 ✓

16 - 7 = 9
Final answer:

The missing number is 7

Applied rules:

• Inverse operations: Addition and subtraction undo each other

• Missing number: Use the inverse operation to find it

• Verification: Always check your answer

• Within 20: All numbers in the problem are ≤ 20

Related Examples:
  • 18 - ? = 11 → 11 + ? = 18 → ? = 7
  • ? - 6 = 10 → 6 + 10 = ? → ? = 16
  • 15 - ? = 8 → 8 + ? = 15 → ? = 7
Quick Tips:
  • Turn subtraction with missing numbers into addition problems
  • Always check your answer by substituting back
  • Use number lines or objects to visualize the problem
Frequently Asked Questions:

Q: How do I solve missing number problems within 20?
A: Use the inverse operation. If subtracting, add the known numbers to find the missing one.

Q: What if the missing number is the first one?
A: For ? - 6 = 10, add the two known numbers: 6 + 10 = 16, so ? = 16.

Solutions: Exercises 6 to 10
6 Subtraction strategies
Exercise 6
What is 19 - 12?
Definition:

Subtraction strategies: Different ways to solve subtraction problems efficiently within 20

Note: Strategies include counting back, using number bonds, or thinking about how many more to reach the first number.

Step-by-step strategy method:
  1. Think about the relationship: 12 + ? = 19
  2. Use number bonds: 12 and 7 make 19
  3. Therefore: 19 - 12 = 7
Original Problem
19 - 12
Number Bond
12 + 7 = 19
Solution
7
Step 1: Think about what goes with 12 to make 19

12 + ? = 19

Step 2: Use number bond knowledge

12 and 7 are partners that make 19

Step 3: Apply to subtraction

If 12 + 7 = 19, then 19 - 12 = 7

19 - 12 = 7
Final answer:

19 - 12 = 7

Applied rules:

• Number bond strategy: Use known partnerships

• Relationship: Addition and subtraction are connected

• Within 20: All numbers in the problem are ≤ 20

Related Examples:
  • 17 - 8: 8 + 9 = 17, so 17 - 8 = 9
  • 15 - 6: 6 + 9 = 15, so 15 - 6 = 9
  • 18 - 11: 11 + 7 = 18, so 18 - 11 = 7
Quick Tips:
  • Know your number bonds to 20 fluently
  • Think "how many more" to reach the first number
  • Use counting back for smaller differences
Frequently Asked Questions:

Q: What are good subtraction strategies within 20?
A: Use number bonds, count back, or think about addition facts.

Q: Should I always use the same strategy?
A: Use the strategy that feels easiest for each problem.

7 Word problem
Exercise 7
Tom had 17 marbles. He gave 8 to his friend. How many marbles does Tom have now?
Definition:

Word problem: A mathematical problem presented in a story format involving subtraction within 20

Note: We need to identify the operation needed to solve the problem within 20.

Step-by-step word problem method:
  1. Read the problem carefully
  2. Identify the starting amount (17 marbles)
  3. Identify what is taken away (8 marbles)
  4. Set up the subtraction: 17 - 8 = ?
  5. Solve: 17 - 8 = 9
Starting Amount
17 marbles
Amount Given Away
8 marbles
Remaining Amount
9 marbles
Step 1: Identify what we know

Tom started with 17 marbles

Step 2: Identify what happened

He gave away 8 marbles

Step 3: Set up the subtraction

17 - 8 = ?

Step 4: Solve

17 - 8 = 9

Step 5: Answer the question

Tom has 9 marbles now

Tom has 9 marbles now
Final answer:

Tom has 9 marbles now

Applied rules:

• Problem solving: Identify key information

• Operation identification: Giving away means subtraction

• Within 20: All quantities in the problem are ≤ 20

• Contextual answer: Include units in your answer

Related Examples:
  • Sarah had 15 pencils, lost 7 → 15 - 7 = 8 pencils left
  • Maria had 14 stickers, used 6 → 14 - 6 = 8 stickers left
  • There were 16 birds, 9 flew away → 16 - 9 = 7 birds left
Quick Tips:
  • Look for keywords like "gave", "took", "used", "left" for subtraction
  • Draw a picture to represent the problem
  • Always answer with a complete sentence
Frequently Asked Questions:

Q: How do I know when to subtract in word problems within 20?
A: Look for words like "gave", "lost", "used", "took", "away", or "left".

Q: What if I'm not sure which operation to use?
A: Think about whether the amount is getting bigger (add) or smaller (subtract).

8 Fact fluency
Exercise 8
What is 14 - 6?
Definition:

Fact fluency: Quick and accurate recall of subtraction facts within 20

Note: Fluency comes from practice and understanding number relationships within 20.

Step-by-step fluency method:
  1. Recognize this as a subtraction fact within 20
  2. Use a strategy: count back from 14 by 6
  3. Or think: 6 + ? = 14
  4. Since 6 + 8 = 14, then 14 - 6 = 8
Original Problem
14 - 6
Number Bond
6 + 8 = 14
Solution
8
Step 1: Recognize the problem type

This is a subtraction fact within 20

Step 2: Use number bond knowledge

Think: what number added to 6 makes 14?

Step 3: Solve

6 + 8 = 14, so 14 - 6 = 8

Step 4: Verify

8 + 6 = 14 ✓

14 - 6 = 8
Final answer:

14 - 6 = 8

Applied rules:

• Fact fluency: Aim for quick recall of basic facts within 20

• Strategies: Use number bonds, counting back, or other methods

• Verification: Check using the inverse operation

• Within 20: All numbers in the problem are ≤ 20

Related Examples:
  • 13 - 5 = 8 (because 5 + 8 = 13)
  • 15 - 7 = 8 (because 7 + 8 = 15)
  • 12 - 4 = 8 (because 4 + 8 = 12)
Quick Tips:
  • Practice regularly to build fluency
  • Use flashcards or games for practice
  • Focus on facts that are challenging for you
Frequently Asked Questions:

Q: What is fact fluency within 20?
A: It's the ability to recall subtraction facts within 20 quickly and accurately.

Q: How can I improve my fact fluency within 20?
A: Practice regularly, use strategies, and play math games to make it fun.

9 Subtraction patterns
Exercise 9
What pattern do you notice in these problems: 18 - 9 = 9, 17 - 8 = 9, 16 - 7 = 9?
Definition:

Subtraction pattern: A consistent relationship between numbers in subtraction problems within 20

Note: Recognizing patterns helps with mental math and fact fluency within 20.

Step-by-step pattern recognition method:
  1. Look at the minuends: 18, 17, 16 (decreasing by 1)
  2. Look at the subtrahends: 9, 8, 7 (decreasing by 1)
  3. Look at the differences: all are 9
  4. Notice the pattern: when both numbers decrease by 1, the answer stays the same
Pattern Sequence
18-9=9, 17-8=9, 16-7=9
Pattern Rule
Same difference when both decrease equally
Next in Pattern
15-6=9
Step 1: Analyze the minuends

They decrease: 18, 17, 16 (each is 1 less than the previous)

Step 2: Analyze the subtrahends

They decrease: 9, 8, 7 (each is 1 less than the previous)

Step 3: Analyze the differences

They stay the same: all are 9

Step 4: Identify the pattern

When minuend and subtrahend both decrease by the same amount, the difference stays constant

When both numbers decrease by the same amount, the difference stays the same
Final answer:

The difference stays at 9 because both the minuend and subtrahend decrease by 1 each time.

Applied rules:

• Pattern recognition: Look for consistent relationships

• Subtraction property: Subtracting the same number from both minuend and subtrahend keeps the difference constant

• Generalization: Apply the pattern to predict next answers

• Within 20: All numbers in the pattern are ≤ 20

Related Examples:
  • 15 - 6 = 9, 14 - 5 = 9, 13 - 4 = 9 (same pattern)
  • 19 - 10 = 9, 18 - 9 = 9, 17 - 8 = 9 (pattern continues)
  • 20 - 11 = 9, 19 - 10 = 9, 18 - 9 = 9 (pattern extends)
Quick Tips:
  • Patterns help you remember multiple facts at once
  • Understanding patterns builds number sense
  • Look for patterns when practicing sets of facts
Frequently Asked Questions:

Q: Why are patterns important in subtraction within 20?
A: Patterns help us predict and understand relationships between numbers.

Q: How do I find patterns in subtraction within 20?
A: Look at how the numbers change in each part of the equation.

10 Mixed practice
Exercise 10
Solve: 15 - 8 + 4
Definition:

Mixed operations: Problems involving more than one operation (subtraction and addition) within 20

Note: When addition and subtraction are in the same problem, we solve from left to right.

Step-by-step mixed operations method:
  1. Solve operations from left to right
  2. First: 15 - 8 = 7
  3. Then: 7 + 4 = 11
Original Problem
15 - 8 + 4
First Operation
15 - 8 = 7
Second Operation
7 + 4 = 11
Final Answer
11
Step 1: Solve the first operation (left to right)

15 - 8 = 7

Step 2: Solve the second operation

Now we have 7 + 4 = 11

Step 3: Final answer

15 - 8 + 4 = 11

15 - 8 + 4 = 11
Final answer:

11

Applied rules:

• Order of operations: For addition and subtraction, go left to right

• Sequential solving: Solve one operation at a time

• Within 20: All numbers in the problem are ≤ 20

• Verification: Check each step as you go

Related Examples:
  • 16 - 9 + 5: First 16 - 9 = 7, then 7 + 5 = 12
  • 13 + 4 - 6: First 13 + 4 = 17, then 17 - 6 = 11
  • 14 - 7 + 8: First 14 - 7 = 7, then 7 + 8 = 15
Quick Tips:
  • For mixed addition and subtraction, work left to right
  • Solve one operation at a time
  • Keep track of your intermediate results
Frequently Asked Questions:

Q: Which operation do I do first in mixed problems within 20?
A: For addition and subtraction, always work from left to right.

Q: What if there are parentheses?
A: Do operations in parentheses first, then left to right for the rest.

Detailed Summary: Subtraction Facts Within 20
Key Concepts and Definitions:

Subtraction within 20: The mathematical operation of taking away one number from another where all numbers (minuend, subtrahend, and difference) are 20 or less. This builds foundational skills for more complex arithmetic.

Minuend: The first number in a subtraction problem; the number from which another number is subtracted (e.g., in 15 - 7 = 8, 15 is the minuend).

Subtrahend: The second number in a subtraction problem; the number that is subtracted from the minuend (e.g., in 15 - 7 = 8, 7 is the subtrahend).

Difference: The answer to a subtraction problem; the result of subtracting one number from another (e.g., in 15 - 7 = 8, 8 is the difference).

Fact Family: A group of related addition and subtraction facts that use the same three numbers, all within 20 (e.g., 7 + 5 = 12, 5 + 7 = 12, 12 - 5 = 7, 12 - 7 = 5).

Core Rules and Principles:
  1. Range Limitation: All numbers in the problem (minuend, subtrahend, and difference) must be 20 or less.
  2. Inverse Relationship: Addition and subtraction are inverse operations; they undo each other.
  3. Order Matters: Unlike addition, subtraction is not commutative (15 - 7 ≠ 7 - 15).
  4. Positive Results: When subtracting a smaller number from a larger number, the result is positive.
  5. Zero Property: Any number minus itself equals zero (a - a = 0).
Effective Strategies:
  • Counting Back: Start with the minuend and count backward by the subtrahend
  • Number Bonds: Think about what number added to the subtrahend equals the minuend
  • Fact Families: Use known addition facts to solve subtraction problems
  • Using Doubles: Leverage known doubles facts (e.g., knowing 10+10=20 helps with 20-10=10)
Common Mistakes to Avoid:
  • Subtracting in the wrong order (confusing minuend and subtrahend)
  • Not checking answers by adding the difference to the subtrahend
  • Forgetting that subtraction is not commutative
  • Getting confused with missing number problems
  • Attempting problems where the subtrahend is larger than the minuend
Memory Techniques:
  • Practice number bonds to 20 regularly
  • Use visual aids like number lines, counters, or drawings
  • Create stories or rhymes to remember challenging facts
  • Play math games that reinforce subtraction facts within 20
Checking Your Work:
  • Add the difference to the subtrahend to verify it equals the minuend
  • Use a different strategy to solve the same problem
  • Estimate to see if your answer makes sense
  • Look for patterns in your answers
Progressive Examples:
  • Simple: 12 - 5 = 7 (counting back from 12)
  • Medium: 17 - 9 = 8 (using number bond: 9 + 8 = 17)
  • Advanced: 19 - 12 = 7 (using fact family: 12 + 7 = 19)
  • Complex: 16 - 8 + 3 = 11 (left-to-right operations)

Key Takeaways for Memorization

  • Subtraction within 20 is the foundation for more complex arithmetic
  • Subtraction is the inverse of addition - use addition facts to solve subtraction
  • Number bonds to 20 are foundational: practice pairs that add up to 11-20
  • Always verify your subtraction by adding the answer to the number you subtracted
  • Understand that order matters in subtraction (unlike addition)
  • All numbers in subtraction within 20 problems must be ≤ 20
Key Laws, Methods, Rules, and Definitions
Minuend - Subtrahend = Difference (where all ≤ 20)
Subtraction Within 20 Structure
Key definitions:

Subtraction within 20: Taking away one number from another where all numbers are 20 or less

Minuend: The first number in subtraction (the number we start with)

Subtrahend: The second number in subtraction (the number we take away)

Difference: The answer to a subtraction problem

Complete methodology:
  1. Identify the problem: Recognize what is being asked
  2. Verify range: Ensure all numbers are within 20
  3. Choose a strategy: Counting back, number bonds, or fact families
  4. Apply the method: Follow the steps of your chosen strategy
  5. Verify the result: Check by adding the difference to the subtrahend
Tip 1: Use number bonds to 20 to help with subtraction facts quickly.
Tip 2: Count back for small numbers being subtracted (like subtracting 1, 2, or 3).
Tip 3: Addition and subtraction are inverse operations; use one to check the other.
Tip 4: Look for patterns in subtraction facts to help with memorization.
Common errors: Subtracting in wrong order, going beyond 20, miscounting.
Fluency building: Practice number bonds, use flashcards, play math games.
Rules to remember:

• Subtraction within 20 means all numbers in the problem are ≤ 20

• Subtraction means to take away or find the difference

• You cannot subtract a larger number from a smaller one at this level

• Addition and subtraction are inverse operations

• For mixed operations, work from left to right

• Always check your work by adding the difference to the subtrahend

Rules and Methods for Subtraction Facts Within 20
a - b = c where a, b, c ≤ 20
Within 20 Constraint
Strategy 1
Counting Back
Start with the first number and count backward
Strategy 2
Number Bonds
Think about what number goes with the subtrahend to make the minuend
Strategy 3
Fact Families
Use related addition facts to solve subtraction

Key Takeaways

  • Subtraction within 20 finds how many are left when we take away
  • All numbers in the problem must be 20 or less
  • Know your number bonds to 20 fluently
  • Addition and subtraction are inverse operations
  • Use multiple strategies to solve subtraction problems
  • Regular practice builds fact fluency

Questions & Answers

Question: I don't understand what "within 20" means. Can you explain?

Answer: "Within 20" means that all the numbers in the subtraction problem (including the answer) are 20 or less. For example, in 15 - 7 = 8:

  • The first number (15) is ≤ 20 ✓
  • The second number (7) is ≤ 20 ✓
  • The answer (8) is ≤ 20 ✓

So all numbers in the problem are within the range of 0 to 20. This helps us focus on learning basic subtraction facts before moving to larger numbers.

Question: My child struggles with subtraction facts within 20. What strategies can help them master these facts?

Answer: Here are effective strategies for mastering subtraction facts within 20:

  • Number Bonds: Help your child learn pairs that add up to numbers within 20 (like 12 = 5 + 7, so 12 - 5 = 7)
  • Counting Back: For 15 - 4, start at 15 and count back 4: 15, 14, 13, 12, 11
  • Fact Families: If they know 8 + 6 = 14, they know 14 - 6 = 8 and 14 - 8 = 6
  • Visual Aids: Use fingers, counters, or drawings to physically remove items

Practice regularly with games, flashcards, or apps. Focus on a few facts at a time rather than overwhelming them with all facts at once.

Remember, memorization comes after understanding, so make sure they understand what subtraction means first.

Question: How can I check if my subtraction answer is right?

Answer: There are several ways to check your subtraction within 20:

  • Addition Check: Add your answer to the number you subtracted. For example, if 15 - 7 = 8, check: 8 + 7 = 15 ✓
  • Counting Up: From your answer, count up to the original number. For 15 - 7 = 8: 8 + 7 = 15 ✓
  • Visual Check: Draw pictures or use objects to represent the problem
  • Estimation: Make sure your answer makes sense. 15 - 7 should be less than 15.

The addition check is the most reliable method because addition and subtraction are inverse operations.

It's always good to check your work, especially when learning new math concepts!

Math Glossary

Subtraction Within 20
Subtraction problems where all numbers (minuend, subtrahend, and difference) are 20 or less.
Minuend
The number from which another number is subtracted; the top number in vertical subtraction.
Subtrahend
The number that is subtracted from the minuend; the bottom number in vertical subtraction.
Difference
The answer to a subtraction problem; the result when one number is subtracted from another.
Fact Family
A group of related addition and subtraction facts using the same three numbers, all within 20, showing the relationship between operations.

Elementary Math Educational Team

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Our team of experienced elementary math teachers and curriculum developers creates research-based, student-friendly subtraction resources. All content is aligned with Common Core State Standards for Mathematics and reviewed by mathematics education experts to ensure accuracy and pedagogical effectiveness for Grade 2 learners.