Equivalent fractions: Fractions that represent the same value or the same portion of a whole, even though they may look different.
- Identify the original fraction
- Choose a number to multiply both numerator and denominator by
- Multiply both parts by the same number
- Verify the result using cross multiplication
Original fraction: \(\frac{2}{3}\)
We'll multiply both parts by 5
Numerator: \(2 \times 5 = 10\)
Denominator: \(3 \times 5 = 15\)
\(\frac{2}{3} = \frac{10}{15}\)
\(2 \times 15 = 30\) and \(3 \times 10 = 30\)
Since both products are equal, the fractions are equivalent
\(\frac{2}{3} = \frac{10}{15}\)
• Multiplication Property: Multiply both numerator and denominator by the same non-zero number
• Identity Property: Multiplying by \(\frac{n}{n} = 1\) doesn't change the value
• Cross Multiplication Test: \(a/b = c/d\) if \(a \times d = b \times c\)
Simplifying fractions: The process of reducing a fraction to its simplest form by dividing both the numerator and denominator by their greatest common factor (GCF).
Factors of 12: 1, 2, 3, 4, 6, 12
Factors of 18: 1, 2, 3, 6, 9, 18
Common factors: 1, 2, 3, 6
Greatest common factor: 6
Numerator: \(12 \div 6 = 2\)
Denominator: \(18 \div 6 = 3\)
\(\frac{12}{18} = \frac{2}{3}\)
\(12 \times 3 = 36\) and \(18 \times 2 = 36\)
Since both products are equal, the fractions are equivalent
\(\frac{12}{18} = \frac{2}{3}\)
• Division Property: Divide both numerator and denominator by the same non-zero number
• Greatest Common Factor (GCF): Largest number that divides both parts evenly
• Simplified Form: When numerator and denominator have no common factors other than 1
Multiple equivalent fractions: There are infinitely many equivalent fractions for any given fraction, generated through various multiplication or division operations.
\(\frac{4}{6}\)
\(\frac{4}{6} = \frac{4 \times 2}{6 \times 2} = \frac{8}{12}\)
\(\frac{4}{6} = \frac{4 \times 3}{6 \times 3} = \frac{12}{18}\)
\(\frac{4}{6} = \frac{4 \div 2}{6 \div 2} = \frac{2}{3}\)
Check \(\frac{4}{6} = \frac{8}{12}\): \(4 \times 12 = 48\) and \(6 \times 8 = 48\) ✓
Check \(\frac{4}{6} = \frac{2}{3}\): \(4 \times 3 = 12\) and \(6 \times 2 = 12\) ✓
Three equivalent fractions: \(\frac{8}{12}, \frac{12}{18}, \frac{2}{3}\)
• Infinite Equivalents: Any fraction has infinitely many equivalent fractions
• Operation Consistency: Always apply the same operation to both numerator and denominator
• Verification: Use cross multiplication to confirm equivalences
Equivalent fractions: Fractions that represent the same value or the same portion of a whole.
Numerator: Top number in a fraction, representing the number of parts taken.
Denominator: Bottom number in a fraction, representing the total number of equal parts.
Greatest Common Factor (GCF): The largest number that divides two or more numbers evenly.
Simplest form: A fraction is in simplest form when the numerator and denominator have no common factors other than 1.
- Multiplication Method: Multiply both numerator and denominator by the same non-zero number
- Division Method: Divide both numerator and denominator by the same non-zero number (to simplify)
• Generating equivalent fractions: \(\frac{a}{b} = \frac{a \times n}{b \times n}\)
• Testing equivalence: \(\frac{a}{b} = \frac{c}{d}\) if \(a \times d = b \times c\)
• Simplifying: \(\frac{a}{b} = \frac{a \div \text{GCF}}{b \div \text{GCF}}\)
Finding missing parts: Use the relationship between equivalent fractions to determine unknown numerators or denominators.
From 6 to 24: \(24 \div 6 = 4\)
So we multiplied the denominator by 4
Original numerator: 5
New numerator: \(5 \times 4 = 20\)
\(\frac{5}{6} = \frac{20}{24}\)
\(5 \times 24 = 120\) and \(6 \times 20 = 120\)
Since both products are equal, the fractions are equivalent
The missing number is 20, so \(\frac{5}{6} = \frac{20}{24}\)
• Consistency Rule: Whatever operation is done to the denominator must also be done to the numerator
• Multiplier Identification: Find the factor by which one denominator was multiplied to get the other
• Cross Multiplication Check: Verify the result by cross multiplying
Simplest form: A fraction is in its simplest form when the numerator and denominator have no common factors other than 1.
Factors of 36: 1, 2, 3, 4, 6, 9, 12, 18, 36
Factors of 48: 1, 2, 3, 4, 6, 8, 12, 16, 24, 48
Common factors: 1, 2, 3, 4, 6, 12
Greatest common factor: 12
Numerator: \(36 \div 12 = 3\)
Denominator: \(48 \div 12 = 4\)
Factors of 3: 1, 3
Factors of 4: 1, 2, 4
Only common factor is 1, so \(\frac{3}{4}\) is in simplest form
Cross multiplication: \(36 \times 4 = 144\) and \(48 \times 3 = 144\) ✓
\(\frac{36}{48} = \frac{3}{4}\) in simplest form
• Greatest Common Factor: Divide by the largest common factor for fastest simplification
• Simplest Form Check: When GCD of numerator and denominator is 1
• Verification: Always check using cross multiplication
Equivalent fractions: Different fractions that represent the same value or the same portion of a whole. They occupy the same position on a number line.
Multiplication method: A technique for generating equivalent fractions by multiplying both the numerator and denominator by the same non-zero number.
Division method: A technique for generating equivalent fractions by dividing both the numerator and denominator by the same non-zero number.
Greatest Common Factor (GCF): The largest number that divides two or more numbers evenly without remainder.
Simplest form: A fraction is in simplest form when the numerator and denominator have no common factors other than 1.
Multiplication Method:
- Identify the original fraction you want to create an equivalent for
- Choose a number to multiply both numerator and denominator by
- Multiply both parts of the fraction by the chosen number
- Verify equivalence using cross multiplication
Division Method:
- Identify the original fraction you want to simplify
- Find the factors of both the numerator and denominator
- Determine the GCF of the numerator and denominator
- Divide both parts of the fraction by the GCF
- Verify equivalence using cross multiplication
• Basic division: \(\frac{a}{b} = \frac{a \div n}{b \div n}\) where n ≠ 0
• Simplification: \(\frac{a}{b} = \frac{a \div \text{GCF}(a,b)}{b \div \text{GCF}(a,b)}\)
• Verification: \(\frac{a}{b} = \frac{c}{d}\) if and only if \(a \times d = b \times c\)
Create an equivalent fraction to \(\frac{1}{4}\) by multiplying by 3:
\(\frac{1}{4} = \frac{1 \times 3}{4 \times 3} = \frac{3}{12}\)
Verification: \(1 \times 12 = 12\) and \(4 \times 3 = 12\) ✓
Simplify \(\frac{15}{25}\) to simplest form:
Factors of 15: 1, 3, 5, 15
Factors of 25: 1, 5, 25
GCF = 5
\(\frac{15}{25} = \frac{15 \div 5}{25 \div 5} = \frac{3}{5}\)
Verification: \(15 \times 5 = 75\) and \(25 \times 3 = 75\) ✓
- Equivalent fractions have the same value but different appearances
- Multiplication method creates larger equivalent fractions
- Division method simplifies fractions to smaller forms
- Always perform the same operation on both numerator and denominator
- Use cross multiplication to verify equivalences
- Simplification makes fractions easier to work with
Solve the following problems using the methods learned in this worksheet:
- Find an equivalent fraction to \(\frac{5}{7}\) by multiplying both parts by 6.
- Simplify \(\frac{20}{30}\) to its simplest form.
- Find the missing number: \(\frac{3}{8} = \frac{?}{32}\)
- List three equivalent fractions for \(\frac{2}{9}\).
- Are \(\frac{10}{15}\) and \(\frac{14}{21}\) equivalent? Show your work.
1. \(\frac{5}{7} = \frac{30}{42}\) (multiply both by 6)
2. \(\frac{20}{30} = \frac{2}{3}\) (divide both by GCF=10)
3. The missing number is 12, so \(\frac{3}{8} = \frac{12}{32}\)
4. Three equivalent fractions: \(\frac{4}{18}, \frac{6}{27}, \frac{8}{36}\) (or others like \(\frac{10}{45}, \frac{12}{54}\))
5. Yes, they are equivalent: \(10 \times 21 = 210\) and \(15 \times 14 = 210\), so cross products are equal.