Basic Addition & Subtraction:
Delve into the foundational concepts of addition and subtraction, explore number bonds and facts, tackle missing numbers, and practice with 50 carefully curated questions suitable for all grade levels.
Basic Addition & Subtraction
Addition and subtraction are the two fundamental operations in arithmetic. They are the building blocks for more complex mathematical concepts and are essential for everyday problem-solving.
Addition
Addition is the process of combining two or more numbers to find their total. The numbers being added are called addends, and the result is known as the sum.
Calculate the sum of 7 and 5:
\[ 7 + 5 = 12 \]
In this example, 7 and 5 are the addends, and 12 is the sum.
Subtraction
Subtraction is the process of finding the difference between two numbers. It involves taking one number away from another. The number from which another number is subtracted is called the minuend, the number being subtracted is the subtrahend, and the result is the difference.
Calculate the difference between 15 and 8:
\[ 15 - 8 = 7 \]
Here, 15 is the minuend, 8 is the subtrahend, and 7 is the difference.
Number Bonds & Facts
Number bonds are a visual representation of the relationship between numbers. They show how numbers can be split into parts or combined to form larger numbers. Understanding number bonds is crucial for mastering addition and subtraction.
Number Bonds to 5
Number bonds to 5 help students understand how numbers can be combined or separated to make 5.
\[ 2 + 3 = 5 \\ 1 + 4 = 5 \\ 0 + 5 = 5 \]
These bonds show the different ways to make 5 by adding two numbers.
Number Bonds to 10
Extending number bonds to 10 allows for a deeper understanding of addition and subtraction, preparing students for more complex arithmetic.
\[ 6 + 4 = 10 \\ 7 + 3 = 10 \\ 2 + 8 = 10 \]
These bonds demonstrate the various combinations to reach 10.
Number Bonds to 20
Number bonds to 20 further enhance students' numerical fluency, aiding in quick mental calculations and problem-solving.
\[ 12 + 8 = 20 \\ 15 + 5 = 20 \\ 10 + 10 = 20 \]
These bonds show how to make 20 using different pairs of numbers.
Number Bonds Facts
Mastering number bonds is essential for developing strong addition and subtraction facts, enabling students to perform calculations more efficiently.
Knowing that: \[ 4 + 6 = 10 \quad \text{and} \quad 10 - 6 = 4 \]
helps in both addition and subtraction, reinforcing the inverse relationship between these operations.
Missing Numbers
Missing numbers problems are a great way to enhance logical thinking and understanding of numerical relationships. These problems require students to determine the unknown number in an equation.
Missing Number in Addition
Find the missing number in the equation:
\[ 7 + \_ = 12 \]
Solution:
\[ \_ = 12 - 7 = 5 \]
So, the missing number is 5.
Missing Number in Subtraction
Find the missing number in the equation:
\[ 15 - \_ = 9 \]
Solution:
\[ \_ = 15 - 9 = 6 \]
So, the missing number is 6.
Missing Number in Equations
Find the missing number in the equation:
\[ \_ + 8 = 14 \]
Solution:
\[ \_ = 14 - 8 = 6 \]
So, the missing number is 6.
Practice Questions
Enhance your understanding of basic addition and subtraction by practicing the following 50 questions. Each question is accompanied by a detailed solution to aid your learning.
Grade 1
Question 1: What is $3 + 2$?
Solution:
\[ 3 + 2 = 5 \]
Question 2: Subtract 1 from 4.
Solution:
\[ 4 - 1 = 3 \]
Question 3: What number is missing: $2 + \_ = 5$?
Solution:
\[ \_ = 5 - 2 = 3 \]
Question 4: What is $5 - 3$?
Solution:
\[ 5 - 3 = 2 \]
Question 5: Add $4 + 1$.
Solution:
\[ 4 + 1 = 5 \]
Grade 2
Question 6: What is $7 + 5$?
Solution:
\[ 7 + 5 = 12 \]
Question 7: Subtract 6 from 14.
Solution:
\[ 14 - 6 = 8 \]
Question 8: What number is missing: $9 + \_ = 15$?
Solution:
\[ \_ = 15 - 9 = 6 \]
Question 9: What is $12 - 7$?
Solution:
\[ 12 - 7 = 5 \]
Question 10: Add $8 + 6$.
Solution:
\[ 8 + 6 = 14 \]
Grade 3
Question 11: What is $15 + 9$?
Solution:
\[ 15 + 9 = 24 \]
Question 12: Subtract 13 from 25.
Solution:
\[ 25 - 13 = 12 \]
Question 13: What number is missing: $18 + \_ = 30$?
Solution:
\[ \_ = 30 - 18 = 12 \]
Question 14: What is $22 - 14$?
Solution:
\[ 22 - 14 = 8 \]
Question 15: Add $19 + 7$.
Solution:
\[ 19 + 7 = 26 \]
Grade 4
Question 16: What is $27 + 14$?
Solution:
\[ 27 + 14 = 41 \]
Question 17: Subtract 19 from 34.
Solution:
\[ 34 - 19 = 15 \]
Question 18: What number is missing: $23 + \_ = 40$?
Solution:
\[ \_ = 40 - 23 = 17 \]
Question 19: What is $36 - 18$?
Solution:
\[ 36 - 18 = 18 \]
Question 20: Add $25 + 19$.
Solution:
\[ 25 + 19 = 44 \]
Grade 5
Question 21: What is $34 + 28$?
Solution:
\[ 34 + 28 = 62 \]
Question 22: Subtract 27 from 50.
Solution:
\[ 50 - 27 = 23 \]
Question 23: What number is missing: $45 + \_ = 60$?
Solution:
\[ \_ = 60 - 45 = 15 \]
Question 24: What is $52 - 29$?
Solution:
\[ 52 - 29 = 23 \]
Question 25: Add $38 + 47$.
Solution:
\[ 38 + 47 = 85 \]
Grade 6
Question 26: What is $58 + 67$?
Solution:
\[ 58 + 67 = 125 \]
Question 27: Subtract 34 from 89.
Solution:
\[ 89 - 34 = 55 \]
Question 28: What number is missing: $76 + \_ = 100$?
Solution:
\[ \_ = 100 - 76 = 24 \]
Question 29: What is $95 - 47$?
Solution:
\[ 95 - 47 = 48 \]
Question 30: Add $64 + 29$.
Solution:
\[ 64 + 29 = 93 \]
Grade 4-5
Question 31: What is $123 + 87$?
Solution:
\[ 123 + 87 = 210 \]
Question 32: Subtract 56 from 132.
Solution:
\[ 132 - 56 = 76 \]
Question 33: What number is missing: $150 + \_ = 200$?
Solution:
\[ \_ = 200 - 150 = 50 \]
Question 34: What is $180 - 99$?
Solution:
\[ 180 - 99 = 81 \]
Question 35: Add $210 + 190$.
Solution:
\[ 210 + 190 = 400 \]
Grade 6-7
Question 36: What is $345 + 678$?
Solution:
\[ 345 + 678 = 1023 \]
Question 37: Subtract 256 from 789.
Solution:
\[ 789 - 256 = 533 \]
Question 38: What number is missing: $500 + \_ = 750$?
Solution:
\[ \_ = 750 - 500 = 250 \]
Question 39: What is $620 - 315$?
Solution:
\[ 620 - 315 = 305 \]
Question 40: Add $455 + 345$.
Solution:
\[ 455 + 345 = 800 \]
Grade 7-8
Question 41: What is $1,234 + 2,345$?
Solution:
\[ 1,234 + 2,345 = 3,579 \]
Question 42: Subtract 1,567 from 3,000.
Solution:
\[ 3,000 - 1,567 = 1,433 \]
Question 43: What number is missing: $2,500 + \_ = 5,000$?
Solution:
\[ \_ = 5,000 - 2,500 = 2,500 \]
Question 44: What is $4,678 - 2,345$?
Solution:
\[ 4,678 - 2,345 = 2,333 \]
Question 45: Add $3,500 + 4,500$.
Solution:
\[ 3,500 + 4,500 = 8,000 \]
Mixed Grades
Question 46: What is $89 + 76$?
Solution:
\[ 89 + 76 = 165 \]
Question 47: Subtract 58 from 130.
Solution:
\[ 130 - 58 = 72 \]
Question 48: What number is missing: $67 + \_ = 100$?
Solution:
\[ \_ = 100 - 67 = 33 \]
Question 49: What is $150 - 75$?
Solution:
\[ 150 - 75 = 75 \]
Question 50: Add $200 + 300$.
Solution:
\[ 200 + 300 = 500 \]
Word Problems Involving Addition & Subtraction
Problem 1: Calculating Total Items
Sarah buys 8 packs of pencils. Each pack contains 12 pencils. How many pencils does Sarah have in total?
To find the total number of pencils, multiply the number of packs by the number of pencils per pack:
\[ 8 \times 12 = 96 \]
Sarah has 96 pencils in total.
Problem 2: Sharing Equally
A teacher has 45 apples and wants to distribute them equally among 9 students. How many apples does each student receive?
To determine how many apples each student gets, divide the total number of apples by the number of students:
\[ 45 \div 9 = 5 \]
Each student receives 5 apples.
Problem 3: Combined Operations
A factory produces 150 widgets each day. How many widgets are produced in a week (7 days)?
Multiply the number of widgets produced each day by the number of days in a week:
\[ 150 \times 7 = 1050 \]
The factory produces 1,050 widgets in a week.
Problem 4: Fractional Division
If 64 candies are divided equally into 8 bags, how many candies are in each bag?
Divide the total number of candies by the number of bags:
\[ 64 \div 8 = 8 \]
Each bag contains 8 candies.
Problem 5: Distributing Resources
There are 100 books to be placed on 5 shelves equally. How many books should be placed on each shelf?
Divide the total number of books by the number of shelves:
\[ 100 \div 5 = 20 \]
Each shelf should have 20 books.
Problem 6: Grouping for Events
At a party, there are 48 balloons to be grouped into sets of 6. How many groups will there be?
Divide the total number of balloons by the group size:
\[ 48 \div 6 = 8 \]
There will be 8 groups of balloons.
Problem 7: Calculating Perimeter
A rectangle has a length of 7 units and a width of 3 units. Calculate its perimeter using addition and multiplication.
The perimeter \( P \) of a rectangle is calculated as:
\[ P = 2 \times (length + width) \]
Substituting the given values:
\[ P = 2 \times (7 + 3) = 2 \times 10 = 20 \text{ units} \]
The perimeter is 20 units.
Problem 8: Scaling Recipes
A recipe requires 3 cups of flour for 4 servings. How much flour is needed for 10 servings?
First, find the amount of flour per serving:
\[ \frac{3 \text{ cups}}{4 \text{ servings}} = 0.75 \text{ cups per serving} \]
Then, multiply by the number of servings:
\[ 0.75 \times 10 = 7.5 \text{ cups} \]
7.5 cups of flour are needed for 10 servings.
Problem 9: Dividing Money
Linda has \$120 and wants to divide it equally among 8 friends. How much does each friend receive?
Divide the total amount by the number of friends:
\[ 120 \div 8 = 15 \]
Each friend receives \$15.
Problem 10: Distributing Seats
A theater has 360 seats divided equally into 12 rows. How many seats are in each row?
Divide the total number of seats by the number of rows:
\[ 360 \div 12 = 30 \]
Each row has 30 seats.
Basic Addition/Subtraction, Number Bonds & Facts: |  | |||||||||||||
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(Shirley Lehmann)
Addition to 8, 9 or 10 Generator 
Number Bonds to 10 
Number Bonds to 100
