Lesson 7.1: Addition and Subtraction up to 20: Number Line & Stories
Use number lines for addition and subtraction within 20 and solve word problems.
⏱️ Reading Time: 15 mins
• ❓ 50 Interactive Practice Questions
#AddSubUpTo20 #NumberLine #WordProblems
Addition and Subtraction up to 20: Number Line & Word Problems
Now let's use the power of the Number Line! We hop forward to add and hop backward to subtract.
10
11
12
13
14
15
+3 Hops Forward! 11 + 3 = 14
Number Line Addition: Hopping forward from 11 by 3 brings us to 14
1. Hopping on the Number Line
• To solve 11 + 3: Start at 11 on the number line. Hop forward 3 steps: 12, 13, 14! So 11 + 3 = 14.
• To solve 15 - 4: Start at 15. Hop backward 4 steps: 14, 13, 12, 11! So 15 - 4 = 11.
Hop Rule: Forward = Addition (+). Backward = Subtraction (-).
2. Simple Real-Life Word Problems
Rani has 12 colored pencils. Her mother gives her 5 more colored pencils. How many pencils does Rani have now? 12 + 5 = 17 pencils!
Steps: 1. Read carefully. 2. Identify numbers. 3. Decide if adding or subtracting. 4. Calculate!
💡 Key Learning Takeaways
- The number line makes adding and subtracting easy visually.
- Hop right/forward to add; hop left/backward to subtract.
- Word problems apply maths to real-life daily stories.
🎯 Key Learning Takeaways
Fluency in addition and subtraction up to 20.
📄 Printable Worksheets (10 Available)
Download ready-to-print PDFs for offline student practice with separate parent/teacher answer keys.
WL-G1-C07-W10
A4 • 15 Qs
Addition and Subtraction up to 20 — Worksheet 10
Curriculum Excellence & Final Review
WL-G1-C07-W09
A4 • 15 Qs
Addition and Subtraction up to 20 — Worksheet 9
Mastery Assessment & Progress Check
WL-G1-C07-W08
A4 • 15 Qs
Addition and Subtraction up to 20 — Worksheet 8
Mixed Review & Reinforcement
WL-G1-C07-W07
A4 • 15 Qs
Addition and Subtraction up to 20 — Worksheet 7
Everyday Applications & Story Maths
WL-G1-C07-W06
A4 • 15 Qs
Addition and Subtraction up to 20 — Worksheet 6
Critical Thinking & Deep Understanding
WL-G1-C07-W05
A4 • 15 Qs
Addition and Subtraction up to 20 — Worksheet 5
Speed Challenge & Quick Check
WL-G1-C07-W04
A4 • 15 Qs
Addition and Subtraction up to 20 — Worksheet 4
Problem Solving & Real-Life Stories
WL-G1-C07-W03
A4 • 15 Qs
Addition and Subtraction up to 20 — Worksheet 3
Hands-on Visual Activity & Matching
WL-G1-C07-W02
A4 • 15 Qs
Addition and Subtraction up to 20 — Worksheet 2
Essential Practice & Skill Builder
WL-G1-C07-W01
A4 • 15 Qs
Addition and Subtraction up to 20 — Worksheet 1
Foundational Concepts & Visual Exploration
✍️ Lesson Practice Questions (50 Questions)
Solve these real-world challenges online, test your understanding, and reveal instant step-by-step explanations.
1
Multiple Choice
Hard
1 Mark
Farmer Dan has 12 sheep. Farmer Ben has 7 sheep. How many sheep must Dan give to Ben so they have different counts by 1?
A
All of them
B
Calculate difference
C
1 sheep
D
None
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
1 sheep
Step-by-Step Explanation:
Adjusting by 1 changes the relative difference by 2.
2
Multiple Choice
Hard
1 Mark
I am a mystery number. If you add 7 to me, you get 19. Then if you subtract 2, what do you get?
A
10
B
14
C
7
D
12
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
10
Step-by-Step Explanation:
The mystery number is 12. Subtracting 2 gives 10.
3
Multiple Choice
Hard
1 Mark
If 12 + 7 = 19, what is 7 + 12?
A
19
B
20
C
7
D
12
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
19
Step-by-Step Explanation:
Addition is commutative: changing the order of addends does not change the sum.
4
Multiple Choice
Hard
1 Mark
Why is 19 greater than 12?
A
Because adding 7 positive items increases the total amount
B
Because it ends with an odd digit
C
Because order doesn't matter
D
Because subtraction makes numbers bigger
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
Because adding 7 positive items increases the total amount
Step-by-Step Explanation:
Adding any non-zero positive number produces a larger total.
5
Multiple Choice
Medium
1 Mark
Sam claims: 'Taking away 7 from 19 gives 26.' What did Sam do wrong?
A
He counted backward
B
He forgot the tens
C
He divided the numbers
D
He added instead of subtracting
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
He added instead of subtracting
Step-by-Step Explanation:
Taking away means subtraction, but Sam performed addition.
6
Multiple Choice
Medium
1 Mark
A student said that 12 + 7 equals 29 because 'we always put 1 in front'. What mistake did the student make?
A
They forgot the decimal
B
They confused adding numbers with writing digits side by side
C
The addition is correct
D
They subtracted instead
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
They confused adding numbers with writing digits side by side
Step-by-Step Explanation:
Place values must be added together, not concatenated blindly.
7
Multiple Choice
Medium
1 Mark
What number completes the pattern: 12, 14, 16, [ ? ]?
A
17
B
18
C
19
D
20
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
18
Step-by-Step Explanation:
The pattern adds 2 each time. 16 + 2 = 18.
8
Multiple Choice
Medium
1 Mark
Find the missing number: 12 + [ ? ] = 19.
A
7
B
6
C
8
D
12
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
7
Step-by-Step Explanation:
Missing number is 7 because 12 + 7 = 19.
9
Multiple Choice
Medium
1 Mark
In a garden, there are 12 red butterflies and 7 blue butterflies. How many butterflies are fluttering together?
A
12 butterflies
B
22 butterflies
C
19 butterflies
D
7 butterflies
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
19 butterflies
Step-by-Step Explanation:
12 + 7 = 19 butterflies.
10
Multiple Choice
Medium
1 Mark
A school library table had 19 storybooks. Students checked out 7 books. How many books remain on the table?
A
13 books
B
7 books
C
12 books
D
11 books
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
12 books
Step-by-Step Explanation:
(19) - 7 = 12 books remain.
11
Multiple Choice
Medium
1 Mark
A baker made 12 blueberry muffins in the morning and 7 chocolate muffins in the afternoon. How many muffins did he bake in all?
A
21 muffins
B
12 muffins
C
19 muffins
D
18 muffins
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
19 muffins
Step-by-Step Explanation:
12 + 7 = 19 muffins baked.
12
Multiple Choice
Easy
1 Mark
What is the result of taking away 7 from 19?
A
11
B
12
C
7
D
13
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
12
Step-by-Step Explanation:
(19) - 7 = 12.
13
Multiple Choice
Easy
1 Mark
Compare the quantities: 17 [ ? ] 14.
A
>
B
=
C
<
D
≈
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
>
Step-by-Step Explanation:
17 is greater than 14.
14
Multiple Choice
Easy
1 Mark
Which number is 1 more than 19?
A
19
B
18
C
20
D
21
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
20
Step-by-Step Explanation:
Adding 1 gives 20.
15
Multiple Choice
Easy
1 Mark
In Chapter 'Addition and Subtraction up to 20', what is 12 + 7?
A
18
B
19
C
21
D
20
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
19
Step-by-Step Explanation:
12 + 7 = 19.
16
Multiple Choice
Hard
1 Mark
Farmer Dan has 11 sheep. Farmer Ben has 4 sheep. How many sheep must Dan give to Ben so they have different counts by 1?
A
None
B
All of them
C
Calculate difference
D
1 sheep
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
1 sheep
Step-by-Step Explanation:
Adjusting by 1 changes the relative difference by 2.
17
Multiple Choice
Hard
1 Mark
I am a mystery number. If you add 4 to me, you get 15. Then if you subtract 2, what do you get?
A
13
B
4
C
11
D
9
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
9
Step-by-Step Explanation:
The mystery number is 11. Subtracting 2 gives 9.
18
Multiple Choice
Hard
1 Mark
If 11 + 4 = 15, what is 4 + 11?
A
16
B
15
C
11
D
4
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
15
Step-by-Step Explanation:
Addition is commutative: changing the order of addends does not change the sum.
19
Multiple Choice
Hard
1 Mark
Why is 15 greater than 11?
A
Because subtraction makes numbers bigger
B
Because adding 4 positive items increases the total amount
C
Because order doesn't matter
D
Because it ends with an odd digit
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
Because adding 4 positive items increases the total amount
Step-by-Step Explanation:
Adding any non-zero positive number produces a larger total.
20
Multiple Choice
Medium
1 Mark
Sam claims: 'Taking away 4 from 15 gives 19.' What did Sam do wrong?
A
He counted backward
B
He divided the numbers
C
He forgot the tens
D
He added instead of subtracting
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
He added instead of subtracting
Step-by-Step Explanation:
Taking away means subtraction, but Sam performed addition.
21
Multiple Choice
Medium
1 Mark
A student said that 11 + 4 equals 25 because 'we always put 1 in front'. What mistake did the student make?
A
They subtracted instead
B
The addition is correct
C
They confused adding numbers with writing digits side by side
D
They forgot the decimal
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
They confused adding numbers with writing digits side by side
Step-by-Step Explanation:
Place values must be added together, not concatenated blindly.
22
Multiple Choice
Medium
1 Mark
What number completes the pattern: 11, 13, 15, [ ? ]?
A
18
B
16
C
19
D
17
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
17
Step-by-Step Explanation:
The pattern adds 2 each time. 15 + 2 = 17.
23
Multiple Choice
Medium
1 Mark
Find the missing number: 11 + [ ? ] = 15.
A
4
B
11
C
3
D
5
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
4
Step-by-Step Explanation:
Missing number is 4 because 11 + 4 = 15.
24
Multiple Choice
Medium
1 Mark
In a garden, there are 11 red butterflies and 4 blue butterflies. How many butterflies are fluttering together?
A
18 butterflies
B
11 butterflies
C
4 butterflies
D
15 butterflies
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
15 butterflies
Step-by-Step Explanation:
11 + 4 = 15 butterflies.
25
Multiple Choice
Medium
1 Mark
A school library table had 15 storybooks. Students checked out 4 books. How many books remain on the table?
A
4 books
B
11 books
C
10 books
D
12 books
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
11 books
Step-by-Step Explanation:
(15) - 4 = 11 books remain.
26
Multiple Choice
Medium
1 Mark
A baker made 11 blueberry muffins in the morning and 4 chocolate muffins in the afternoon. How many muffins did he bake in all?
A
17 muffins
B
14 muffins
C
11 muffins
D
15 muffins
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
15 muffins
Step-by-Step Explanation:
11 + 4 = 15 muffins baked.
27
Multiple Choice
Easy
1 Mark
What is the result of taking away 4 from 15?
A
12
B
4
C
11
D
10
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
11
Step-by-Step Explanation:
(15) - 4 = 11.
28
Multiple Choice
Easy
1 Mark
Compare the quantities: 16 [ ? ] 13.
A
>
B
<
C
≈
D
=
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
>
Step-by-Step Explanation:
16 is greater than 13.
29
Multiple Choice
Easy
1 Mark
Which number is 1 more than 15?
A
14
B
15
C
17
D
16
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
16
Step-by-Step Explanation:
Adding 1 gives 16.
30
Multiple Choice
Easy
1 Mark
In Chapter 'Addition and Subtraction up to 20', what is 11 + 4?
A
14
B
17
C
15
D
16
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
15
Step-by-Step Explanation:
11 + 4 = 15.
31
Multiple Choice
Hard
1 Mark
Farmer Dan has 10 sheep. Farmer Ben has 9 sheep. How many sheep must Dan give to Ben so they have different counts by 1?
A
None
B
Calculate difference
C
1 sheep
D
All of them
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
1 sheep
Step-by-Step Explanation:
Adjusting by 1 changes the relative difference by 2.
32
Multiple Choice
Hard
1 Mark
I am a mystery number. If you add 9 to me, you get 19. Then if you subtract 2, what do you get?
A
8
B
10
C
12
D
9
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
8
Step-by-Step Explanation:
The mystery number is 10. Subtracting 2 gives 8.
33
Multiple Choice
Hard
1 Mark
If 10 + 9 = 19, what is 9 + 10?
A
19
B
9
C
10
D
20
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
19
Step-by-Step Explanation:
Addition is commutative: changing the order of addends does not change the sum.
34
Multiple Choice
Hard
1 Mark
Why is 19 greater than 10?
A
Because adding 9 positive items increases the total amount
B
Because subtraction makes numbers bigger
C
Because order doesn't matter
D
Because it ends with an odd digit
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
Because adding 9 positive items increases the total amount
Step-by-Step Explanation:
Adding any non-zero positive number produces a larger total.
35
Multiple Choice
Medium
1 Mark
Sam claims: 'Taking away 9 from 19 gives 28.' What did Sam do wrong?
A
He divided the numbers
B
He forgot the tens
C
He counted backward
D
He added instead of subtracting
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
He added instead of subtracting
Step-by-Step Explanation:
Taking away means subtraction, but Sam performed addition.
36
Multiple Choice
Medium
1 Mark
A student said that 10 + 9 equals 29 because 'we always put 1 in front'. What mistake did the student make?
A
They forgot the decimal
B
They confused adding numbers with writing digits side by side
C
They subtracted instead
D
The addition is correct
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
They confused adding numbers with writing digits side by side
Step-by-Step Explanation:
Place values must be added together, not concatenated blindly.
37
Multiple Choice
Medium
1 Mark
What number completes the pattern: 10, 12, 14, [ ? ]?
A
16
B
18
C
17
D
15
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
16
Step-by-Step Explanation:
The pattern adds 2 each time. 14 + 2 = 16.
38
Multiple Choice
Medium
1 Mark
Find the missing number: 10 + [ ? ] = 19.
A
10
B
8
C
10
D
9
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
9
Step-by-Step Explanation:
Missing number is 9 because 10 + 9 = 19.
39
Multiple Choice
Medium
1 Mark
In a garden, there are 10 red butterflies and 9 blue butterflies. How many butterflies are fluttering together?
A
9 butterflies
B
19 butterflies
C
22 butterflies
D
10 butterflies
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
19 butterflies
Step-by-Step Explanation:
10 + 9 = 19 butterflies.
40
Multiple Choice
Medium
1 Mark
A school library table had 19 storybooks. Students checked out 9 books. How many books remain on the table?
A
11 books
B
9 books
C
9 books
D
10 books
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
10 books
Step-by-Step Explanation:
(19) - 9 = 10 books remain.
41
Multiple Choice
Medium
1 Mark
A baker made 10 blueberry muffins in the morning and 9 chocolate muffins in the afternoon. How many muffins did he bake in all?
A
10 muffins
B
21 muffins
C
19 muffins
D
18 muffins
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
19 muffins
Step-by-Step Explanation:
10 + 9 = 19 muffins baked.
42
Multiple Choice
Easy
1 Mark
What is the result of taking away 9 from 19?
A
9
B
11
C
9
D
10
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
10
Step-by-Step Explanation:
(19) - 9 = 10.
43
Multiple Choice
Easy
1 Mark
Compare the quantities: 15 [ ? ] 12.
A
>
B
<
C
=
D
≈
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
>
Step-by-Step Explanation:
15 is greater than 12.
44
Multiple Choice
Easy
1 Mark
Which number is 1 more than 19?
A
19
B
18
C
20
D
21
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
20
Step-by-Step Explanation:
Adding 1 gives 20.
45
Multiple Choice
Easy
1 Mark
In Chapter 'Addition and Subtraction up to 20', what is 10 + 9?
A
18
B
19
C
21
D
20
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
19
Step-by-Step Explanation:
10 + 9 = 19.
46
Multiple Choice
Hard
1 Mark
Farmer Dan has 9 sheep. Farmer Ben has 6 sheep. How many sheep must Dan give to Ben so they have different counts by 1?
A
Calculate difference
B
All of them
C
None
D
1 sheep
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
1 sheep
Step-by-Step Explanation:
Adjusting by 1 changes the relative difference by 2.
47
Multiple Choice
Hard
1 Mark
I am a mystery number. If you add 6 to me, you get 15. Then if you subtract 2, what do you get?
A
9
B
6
C
11
D
7
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
7
Step-by-Step Explanation:
The mystery number is 9. Subtracting 2 gives 7.
48
Multiple Choice
Hard
1 Mark
If 9 + 6 = 15, what is 6 + 9?
A
16
B
6
C
9
D
15
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
15
Step-by-Step Explanation:
Addition is commutative: changing the order of addends does not change the sum.
49
Multiple Choice
Hard
1 Mark
Why is 15 greater than 9?
A
Because subtraction makes numbers bigger
B
Because order doesn't matter
C
Because adding 6 positive items increases the total amount
D
Because it ends with an odd digit
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
Because adding 6 positive items increases the total amount
Step-by-Step Explanation:
Adding any non-zero positive number produces a larger total.
50
Multiple Choice
Medium
1 Mark
Sam claims: 'Taking away 6 from 15 gives 21.' What did Sam do wrong?
A
He divided the numbers
B
He added instead of subtracting
C
He forgot the tens
D
He counted backward
💡 Click to View Correct Answer & Explanation ▼
Correct Answer:
He added instead of subtracting
Step-by-Step Explanation:
Taking away means subtraction, but Sam performed addition.