Solved Exercises on One-Step Word Problems All Operations in Grade 3

Master one-step word problems with all operations: addition, subtraction, multiplication, division, and mixed operations through these 10 detailed exercises.

Solution: Exercises 1 to 3
1 Addition problem
Exercise 1
Sarah has 12 stickers. Her friend gives her 8 more stickers. How many stickers does Sarah have now?
Definition:

Addition word problem: Finding the total when combining two or more quantities

Solution method:
  1. Identify the numbers involved: 12 and 8
  2. Recognize the operation needed: addition (combining quantities)
  3. Add the numbers together
Starting amount
12 stickers
Added amount
+ 8 stickers
Total
20 stickers
Step 1: Identify what we know

Sarah starts with 12 stickers

Her friend gives her 8 more stickers

Step 2: Determine the operation

Keywords: "more", "now" indicate addition

Step 3: Perform the calculation

12 + 8 = 20

Step 4: State the answer in context

Sarah has 20 stickers now

12 + 8 = 20 stickers
Final answer:

Sarah has 20 stickers now

Applied rules:

• Keyword identification: Look for words indicating addition

• Operation selection: Choose addition for combining quantities

• Calculation: Add the numbers together

2 Subtraction problem
Exercise 2
Tom had 25 marbles. He gave 9 marbles to his sister. How many marbles does Tom have left?
Definition:

Subtraction word problem: Finding what remains after taking away a quantity

Starting amount
25 marbles
Amount taken away
- 9 marbles
Remaining
16 marbles
Step 1: Identify what we know

Tom started with 25 marbles

He gave away 9 marbles

Step 2: Determine the operation

Keywords: "gave", "left" indicate subtraction

Step 3: Perform the calculation

25 - 9 = 16

Step 4: State the answer in context

Tom has 16 marbles left

25 - 9 = 16 marbles
Final answer:

Tom has 16 marbles left

Applied rules:

• Keyword identification: Look for words indicating subtraction

• Operation selection: Choose subtraction for taking away

• Calculation: Subtract the smaller number from the larger

3 Multiplication problem
Exercise 3
There are 4 bags of apples. Each bag has 6 apples. How many apples are there in total?
Definition:

Multiplication word problem: Finding the total when equal groups are combined

Number of groups
4 bags
Items per group
× 6 apples
Total
24 apples
Step 1: Identify what we know

There are 4 bags

Each bag has 6 apples

Step 2: Determine the operation

Keywords: "each", "total" indicate multiplication

Step 3: Perform the calculation

4 × 6 = 24

Step 4: State the answer in context

There are 24 apples in total

4 × 6 = 24 apples
Final answer:

There are 24 apples in total

Applied rules:

• Keyword identification: Look for words indicating equal groups

• Operation selection: Choose multiplication for repeated addition

• Calculation: Multiply the number of groups by items per group

Solution: Exercises 4 to 5
4 Division problem
Exercise 4
Maria has 18 cookies. She wants to share them equally among 6 friends. How many cookies will each friend get?
Definition:

Division word problem: Finding how many equal parts or groups can be made

Total items
18 cookies
Number of groups
÷ 6 friends
Per group
3 cookies
Step 1: Identify what we know

Maria has 18 cookies

She wants to share them equally among 6 friends

Step 2: Determine the operation

Keywords: "equally", "each" indicate division

Step 3: Perform the calculation

18 ÷ 6 = 3

Step 4: State the answer in context

Each friend will get 3 cookies

18 ÷ 6 = 3 cookies per friend
Final answer:

Each friend will get 3 cookies

Applied rules:

• Keyword identification: Look for words indicating sharing equally

• Operation selection: Choose division for equal sharing

• Calculation: Divide the total by the number of groups

5 Comparison problem
Exercise 5
Jake read 32 pages of a book. Emma read 25 pages of the same book. How many more pages did Jake read than Emma?
Definition:

Comparison word problem: Finding the difference between two quantities

Jake's pages
32 pages
Emma's pages
- 25 pages
Difference
7 pages
Step 1: Identify what we know

Jake read 32 pages

Emma read 25 pages

Step 2: Determine the operation

Keywords: "more", "than" indicate subtraction (finding difference)

Step 3: Perform the calculation

32 - 25 = 7

Step 4: State the answer in context

Jake read 7 more pages than Emma

32 - 25 = 7 more pages
Final answer:

Jake read 7 more pages than Emma

Applied rules:

• Keyword identification: Look for words comparing quantities

• Operation selection: Choose subtraction for "how many more"

• Calculation: Subtract the smaller number from the larger

All Operations Rules
Addition: A + B = C
Combining Quantities
Subtraction: A - B = C
Taking Away or Finding Difference
Multiplication: A × B = C
Equal Groups or Repeated Addition
Division: A ÷ B = C
Sharing Equally or Finding Groups
+
Addition
more, total, altogether, sum, increase, combine
-
Subtraction
less, fewer, left, difference, decrease, take away
×
Multiplication
each, groups of, times, product, double, triple
÷
Division
each, shared equally, per, split, quotient, distribute
1
Read the problem carefully
2
Identify key numbers and information
3
Find keywords that suggest the operation
4
Set up the equation
5
Solve and check your answer
Key Concept: Operation Keywords

Learning to recognize keywords helps determine which operation to use in word problems.

Common Problem Types
  • Addition: combining, total, altogether
  • Subtraction: taking away, difference, remaining
  • Multiplication: equal groups, repeated addition
  • Division: sharing equally, finding groups
🍎
Addition: More apples
🍊
Subtraction: Fewer oranges
🍌
Multiplication: Groups of bananas
🍇
Division: Sharing grapes
Complete Guide to All Operations Word Problems
Read → Think → Solve → Check
Problem Solving Process
Key definitions:

Word problem: A mathematical question presented in narrative form

One-step problem: A problem requiring only one mathematical operation to solve

Keywords: Words that indicate which mathematical operation to use

Complete methodology:
  1. Read carefully: Understand the situation described
  2. Identify information: Find numbers and important details
  3. Look for keywords: Determine the required operation
  4. Set up equation: Write the mathematical expression
  5. Solve: Calculate the answer
  6. Check: Verify the answer makes sense
Tip 1: Draw pictures or use manipulatives to visualize the problem.
Tip 2: Underline or circle important numbers and keywords.
Tip 3: Always write your answer in a complete sentence.
Tip 4: Estimate your answer before calculating to check reasonableness.
Common errors: Misreading the question, choosing wrong operation, calculation mistakes.
Success strategies: Practice keyword recognition, use visual aids, check work.
Key rules to remember:

• Addition: combines quantities ("more", "total", "altogether")

• Subtraction: finds difference or remaining ("less", "left", "fewer")

• Multiplication: equal groups or repeated addition ("each", "groups of")

• Division: sharing equally or finding groups ("each", "shared", "per")

All Operations Word Problems

+
Addition
more, total, altogether, sum, increase, combine
-
Subtraction
less, fewer, left, difference, decrease, take away
×
Multiplication
each, groups of, times, product, double, triple
÷
Division
each, shared equally, per, split, quotient, distribute
1
Read the entire problem
2
Circle numbers and underline keywords
3
Choose the correct operation
4
Solve and write the answer in a sentence

Questions & Answers

Question: How do I know whether to add, subtract, multiply, or divide in a word problem?

Answer: Look for these key actions in the problem:

  • Addition: Something is being added, combined, or increased
  • Subtraction: Something is being taken away, compared, or decreased
  • Multiplication: Equal groups, repeated addition, or "each" situations
  • Division: Sharing equally, splitting into groups, or "each" situations

Always consider what the problem is asking and whether the result should be larger (addition/multiplication) or smaller (subtraction/division).

Question: When should I use multiplication instead of addition in word problems?

Answer: Use multiplication when you see equal groups or repeated addition:

  • Keywords like "each", "times", "groups of", "product" suggest multiplication
  • If you're adding the same number multiple times, it's multiplication

Example: "There are 4 boxes with 5 pencils each" → 4 × 5 = 20

This is the same as 5 + 5 + 5 + 5 = 20, but multiplication is faster.

If the groups aren't equal, use addition instead.

Question: How can I check if my answer to a word problem is reasonable?

Answer: There are several ways to verify your answer:

  • Estimate: Round numbers and do a quick mental calculation
  • Re-read: Check if your answer fits the story in the problem
  • Reverse operation: If you added, subtract to check; if you multiplied, divide to check

For example, if you found that Sarah has 20 apples after starting with 12 and getting 8 more, check: 12 + 8 = 20 ✓

Always ask yourself: "Does this answer make sense in the context of the problem?"

Complete Summary: One-Step Word Problems All Operations

Definitions of Key Concepts

Word Problem: A mathematical question presented in narrative form using everyday situations.

One-Step Problem: A problem that requires only one mathematical operation (addition, subtraction, multiplication, or division) to solve.

Keywords: Words that indicate which mathematical operation to use (e.g., "more" suggests addition, "left" suggests subtraction).

Operations: Addition (+), subtraction (-), multiplication (×), and division (÷) used to solve mathematical problems.

Addition: The process of combining two or more quantities to find a total.

Subtraction: The process of taking away one quantity from another to find the difference or remaining amount.

Multiplication: The process of finding the total when equal groups are combined (repeated addition).

Division: The process of sharing equally or splitting into equal groups.

Core Rules and Principles

Addition: Used when combining quantities, finding totals, or increasing amounts. Keywords: more, total, altogether, sum, increase.

Subtraction: Used when taking away, finding differences, or determining what remains. Keywords: less, fewer, left, difference, decrease.

Multiplication: Used for equal groups, repeated addition, or finding totals of identical sets. Keywords: each, groups of, times, product.

Division: Used for sharing equally, finding equal parts, or determining how many groups. Keywords: each, shared equally, per, distributed.

Problem-Solving Process: Read the problem, identify important information, determine the operation, set up the equation, solve, and check your answer.

Reasonableness Check: Always verify that your answer makes sense in the context of the problem.

Step-by-Step Method
  1. Read Carefully: Understand the situation described in the problem.
  2. Identify Information: Find numbers and important details.
  3. Look for Keywords: Determine which operation to use based on clue words.
  4. Set Up Equation: Write the mathematical expression that represents the problem.
  5. Solve: Calculate the answer using the appropriate operation.
  6. Check: Verify that your answer makes sense in the context of the problem.
Examples (Simple to Advanced)

Simple Addition: "Tom has 3 apples. He gets 2 more. How many does he have?" (3 + 2 = 5)

Simple Subtraction: "Sarah has 8 cookies. She eats 3. How many are left?" (8 - 3 = 5)

Simple Multiplication: "There are 4 bags with 3 candies each. How many candies total?" (4 × 3 = 12)

Simple Division: "12 cookies shared equally among 4 friends. How many each?" (12 ÷ 4 = 3)

Advanced Comparison: "Jake read 25 pages. Emma read 18 pages. How many more did Jake read?" (25 - 18 = 7)

Advanced Multiplication: "A farmer has 5 rows of trees. Each row has 8 trees. How many trees total?" (5 × 8 = 40)

Tips, Tricks, and Common Pitfalls

Tips: Draw pictures to visualize the problem; underline important numbers; circle keywords; estimate your answer first.

Tricks: Remember that "more than" often means subtraction for comparison problems; "in all" usually means addition.

Common Pitfalls: Choosing the wrong operation due to misreading keywords; forgetting to include units in your answer; not checking if the answer makes sense.

Memory Aid: "ASMD" - Addition, Subtraction, Multiplication, Division. Think of the action: Adding, Taking away, Making groups, Sharing equally.

Checking Strategy: Always verify by performing the reverse operation.

Key Notes for Memorization

Addition Keywords: more, total, altogether, sum, combined, increased by, in all.

Subtraction Keywords: less, fewer, left, difference, decrease, take away, how many more, how many fewer.

Multiplication Keywords: each, groups of, times, product, twice, double, triple.

Division Keywords: each, per, shared equally, distributed, quotient, split evenly.

Always Remember: Write your final answer in a complete sentence that addresses the question asked.

Visual Representation: Use drawings or manipulatives to model the problem situation.

Estimation Strategy: Round numbers to check if your answer is reasonable.