Problems Using Fractions - Mathematics - Exercises with solutions

Master fraction applications: word problems, fraction operations, and real-life applications through these 10 detailed exercises.

Exercises 1 to 10
1 Fraction word problem
Exercise 1
Emma has 12 cookies. She ate 3 cookies. What fraction of the cookies did she eat?
Solution:

Emma started with 12 cookies total.

She ate 3 cookies.

The fraction she ate is 3 out of 12, or 3/12.

This can be simplified by dividing both numerator and denominator by 3: 3/12 = 1/4.

Answer: 3/12 or 1/4
2 Fraction word problem
Exercise 2
A pizza is cut into 8 equal slices. If 5 slices are eaten, what fraction of the pizza is left?
Solution:

The pizza is cut into 8 slices total.

5 slices were eaten.

So 8 - 5 = 3 slices are left.

The fraction left is 3/8.

Answer: 3/8
3 Fraction addition problem
Exercise 3
Sarah ate 1/4 of a cake. Her brother ate 1/4 of the same cake. What fraction of the cake did they eat altogether?
Solution:

Sarah ate 1/4 of the cake.

Her brother ate 1/4 of the cake.

Together they ate 1/4 + 1/4 = 2/4.

This can be simplified: 2/4 = 1/2.

Answer: 2/4 or 1/2
4 Fraction subtraction problem
Exercise 4
A chocolate bar has 6 equal pieces. If 2 pieces are eaten, what fraction of the chocolate bar remains?
Solution:

The chocolate bar has 6 pieces total.

2 pieces were eaten.

So 6 - 2 = 4 pieces remain.

The fraction remaining is 4/6.

This can be simplified: 4/6 = 2/3.

Answer: 4/6 or 2/3
5 Fraction comparison problem
Exercise 5
John ate 1/3 of a sandwich and Mary ate 1/4 of the same sandwich. Who ate more?
Solution:

John ate 1/3 of the sandwich.

Mary ate 1/4 of the sandwich.

When comparing fractions with the same numerator (both have 1), the fraction with the smaller denominator is larger.

Since 3 is smaller than 4, 1/3 is larger than 1/4.

So John ate more.

Answer: John ate more (1/3 > 1/4)
6 Fraction word problem
Exercise 6
There are 10 students in a class. 6 of them are girls. What fraction of the class are boys?
Solution:

There are 10 students total.

6 of them are girls.

So 10 - 6 = 4 are boys.

The fraction of boys is 4/10.

This can be simplified: 4/10 = 2/5.

Answer: 4/10 or 2/5
7 Fraction addition problem
Exercise 7
Tom walked 1/2 mile to school. After school, he walked 1/4 mile to the library. How far did he walk in total?
Solution:

Tom walked 1/2 mile to school.

He walked 1/4 mile to the library.

Find a common denominator: LCD of 2 and 4 is 4.

Convert 1/2 to equivalent fraction: 1/2 = 2/4.

Total distance: 2/4 + 1/4 = 3/4 mile.

Answer: 3/4 mile
8 Fraction word problem
Exercise 8
A basket contains 15 apples. 5 of them are red, 4 are green, and the rest are yellow. What fraction of the apples are yellow?
Solution:

There are 15 apples total.

5 are red and 4 are green.

So 5 + 4 = 9 are red or green.

Yellow apples: 15 - 9 = 6.

The fraction that are yellow is 6/15.

This can be simplified: 6/15 = 2/5.

Answer: 6/15 or 2/5
9 Fraction comparison problem
Exercise 9
A recipe calls for 2/3 cup of flour and 1/2 cup of sugar. Which ingredient is used in a larger amount?
Solution:

The recipe uses 2/3 cup of flour.

The recipe uses 1/2 cup of sugar.

Find a common denominator: LCD of 3 and 2 is 6.

Convert fractions: 2/3 = 4/6, 1/2 = 3/6.

Since 4/6 > 3/6, flour is used in a larger amount.

Answer: Flour (2/3 cup) is more than sugar (1/2 cup)
10 Multi-step fraction problem
Exercise 10
A farmer has 24 animals. 1/3 are cows, 1/4 are sheep, and the rest are chickens. How many chickens does the farmer have?
Solution:

The farmer has 24 animals total.

Cows: 1/3 of 24 = 8 cows.

Sheep: 1/4 of 24 = 6 sheep.

Cows + Sheep = 8 + 6 = 14.

Chickens: 24 - 14 = 10.

The fraction of chickens is 10/24 = 5/12.

Answer: 10 chickens (5/12 of the animals)
Detailed Summary of Problems Using Fractions
Key Definitions:

Fraction Word Problem: A real-life situation that requires understanding and applying fraction concepts to solve

Part-to-Whole Relationship: The relationship between a part and the whole, expressed as a fraction

Remainder: What is left after a portion has been taken away from the whole

Common Denominator: A shared denominator that allows fractions with different denominators to be compared or combined

Unit Fraction: A fraction with numerator 1

Core Methods:
  1. Identify Total Amount: Determine the whole or total quantity in the problem
  2. Identify Part Taken: Determine the specific portion or parts being considered
  3. Form Fraction: Express the part over the whole as a fraction
  4. Simplify if Possible: Reduce the fraction to its lowest terms
  5. Perform Operations: Add, subtract, or compare fractions as needed
Tip 1: Always identify the total amount first when solving fraction word problems.
Tip 2: For addition/subtraction of fractions with different denominators, find a common denominator first.
Tip 3: When comparing fractions with the same numerator, the one with the smaller denominator is larger.
Tip 4: Draw pictures or use visual models to help understand the problem.
Tip 5: Always simplify fractions to their lowest terms when possible.
Core Rule: The fraction representing a part of a whole is always the part divided by the whole.
Memory Aid: "Part over whole" - the numerator is always the specific portion being considered.
Common Mistake: Confusing the part with the whole when forming fractions.
Essential Rules:

• Fraction = Part / Whole

• To add/subtract fractions with different denominators, find a common denominator first

• When comparing fractions with same numerator, smaller denominator = larger fraction

• When comparing fractions with same denominator, larger numerator = larger fraction

• Always simplify fractions to lowest terms

• Remainder = Whole - Part taken

Examples:
  • Simple: 3 out of 10 students = 3/10
  • Medium: 1/4 + 1/4 = 2/4 = 1/2
  • Advanced: 2/3 vs 3/4 → LCD is 12 → 8/12 vs 9/12 → 3/4 is larger
  • Real-life: 1/2 hour + 1/4 hour = 3/4 hour
  • Multi-step: If 1/3 of 12 items are red, then 12 - 4 = 8 are not red
Common Pitfalls to Avoid:
  • Reversing the numerator and denominator when forming fractions
  • Adding numerators and denominators separately without finding common denominators
  • Forgetting to simplify fractions to lowest terms
  • Making errors when finding common denominators
  • Not identifying the correct total amount in word problems
  • Confusing what the fraction represents in the context of the problem
Visual Fraction Problem Solving Reference
\(\text{Fraction} = \frac{\text{Part}}{\text{Whole}}\)
Fraction Formula
Step 1
Identify Whole
Total amount in problem
Step 2
Identify Part
Amount being considered
Step 3
Form Fraction
Part over whole
Step 4
Simplify
Reduce to lowest terms

Key Takeaways

  • Fraction word problems require identifying the whole and the specific part
  • Always form fractions as part over whole
  • For operations with different denominators, find common denominators first
  • Visual models help understand the problem context
  • Remainders are calculated as whole minus part taken
  • Always simplify fractions when possible
  • Check that your answer makes sense in the context of the problem