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: \(\frac{3}{5}\)
We'll multiply both parts by 4
Numerator: \(3 \times 4 = 12\)
Denominator: \(5 \times 4 = 20\)
\(\frac{3}{5} = \frac{12}{20}\)
\(3 \times 20 = 60\) and \(5 \times 12 = 60\)
Since both products are equal, the fractions are equivalent
\(\frac{3}{5} = \frac{12}{20}\)
• 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 \(a \times d = b \times c\)
Generating equivalent fractions: Creating new fractions that have the same value as the original by multiplying both the numerator and denominator by the same non-zero number.
Original fraction: \(\frac{4}{7}\)
We'll multiply both parts by 6
Numerator: \(4 \times 6 = 24\)
Denominator: \(7 \times 6 = 42\)
\(\frac{4}{7} = \frac{24}{42}\)
\(4 \times 42 = 168\) and \(7 \times 24 = 168\)
Since both products are equal, the fractions are equivalent
\(\frac{4}{7} = \frac{24}{42}\)
• Multiplication Property: Multiply both numerator and denominator by the same non-zero number
• Value Preservation: The fraction's value remains unchanged
• Verification: Use cross multiplication to confirm equivalence
Multiple equivalent fractions: There are infinitely many equivalent fractions for any given fraction, generated through various multiplication operations.
\(\frac{2}{3}\)
\(\frac{2}{3} = \frac{2 \times 2}{3 \times 2} = \frac{4}{6}\)
\(\frac{2}{3} = \frac{2 \times 3}{3 \times 3} = \frac{6}{9}\)
\(\frac{2}{3} = \frac{2 \times 4}{3 \times 4} = \frac{8}{12}\)
Check \(\frac{2}{3} = \frac{6}{9}\): \(2 \times 9 = 18\) and \(3 \times 6 = 18\) ✓
Any number can be used as a multiplier to generate equivalent fractions
Three equivalent fractions: \(\frac{4}{6}, \frac{6}{9}, \frac{8}{12}\)
• 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.
Multiplication method: Technique for generating equivalent fractions by multiplying both numerator and denominator by the same non-zero number.
- 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
• Generating equivalent fractions: \(\frac{a}{b} = \frac{a \times n}{b \times n}\)
• Testing equivalence: \(\frac{a}{b} = \frac{c}{d}\) if \(a \times d = b \times c\)
• Identity property: \(\frac{a}{b} \times \frac{n}{n} = \frac{a}{b}\)
Finding missing parts: Use the relationship between equivalent fractions to determine unknown numerators or denominators.
From 4 to 20: \(20 \div 4 = 5\)
So we multiplied the denominator by 5
Original numerator: 3
New numerator: \(3 \times 5 = 15\)
\(\frac{3}{4} = \frac{15}{20}\)
\(3 \times 20 = 60\) and \(4 \times 15 = 60\)
Since both products are equal, the fractions are equivalent
The missing number is 15, so \(\frac{3}{4} = \frac{15}{20}\)
• 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
Word problem application: Converting real-world situations into mathematical fractions and then applying multiplication to generate equivalent fractions.
2 slices eaten out of 6 total slices
This is \(\frac{2}{6}\)
Numerator: \(2 \times 4 = 8\)
Denominator: \(6 \times 4 = 24\)
\(\frac{2}{6} = \frac{8}{24}\)
Cross multiplication: \(2 \times 24 = 48\) and \(6 \times 8 = 48\) ✓
\(\frac{2}{6}\) and \(\frac{8}{24}\) represent the same amount of pizza eaten
\(\frac{2}{6} = \frac{8}{24}\) of the pizza was eaten
• Problem Translation: Convert real-world ratios to mathematical fractions
• Multiplication Application: Use multiplication method to generate equivalent fractions
• Contextual Interpretation: Understand the meaning of the equivalent fraction
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.
Numerator: The top number in a fraction; tells how many parts are being considered.
Denominator: The bottom number in a fraction; tells how many equal parts the whole is divided into.
- 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
• Multiplication Property: \(\frac{a}{b} = \frac{a \times n}{b \times n}\) where n ≠ 0
• Identity Property: \(\frac{a}{b} \times \frac{n}{n} = \frac{a}{b}
• Equivalence Test: \(\frac{a}{b} = \frac{c}{d}\) if and only if \(a \times d = b \times c\)
Find an equivalent fraction to \(\frac{1}{2}\) by multiplying by 3:
\(\frac{1}{2} = \frac{1 \times 3}{2 \times 3} = \frac{3}{6}
Verification: \(1 \times 6 = 6\) and \(2 \times 3 = 6\) ✓
Find an equivalent fraction to \(\frac{4}{5}\) by multiplying by 7:
\(\frac{4}{5} = \frac{4 \times 7}{5 \times 7} = \frac{28}{35}
Verification: \(4 \times 35 = 140\) and \(5 \times 28 = 140\) ✓
Find the missing number: \(\frac{5}{8} = \frac{?}{40}
From 8 to 40: \(40 \div 8 = 5
Apply to numerator: \(5 \times 5 = 25
\(\frac{5}{8} = \frac{25}{40}
Verification: \(5 \times 40 = 200\) and \(8 \times 25 = 200\) ✓
- Equivalent fractions have the same value but different appearances
- Multiplication method creates larger equivalent fractions
- Always multiply both numerator and denominator by the same number
- Use cross multiplication to verify equivalences
- Any non-zero number can be used as a multiplier
- The value of the fraction remains unchanged during multiplication
- There are infinitely many equivalent fractions for any given fraction
Solve the following problems using the multiplication method:
- Find an equivalent fraction to \(\frac{5}{6}\) by multiplying both parts by 3.
- Find an equivalent fraction to \(\frac{3}{8}\) by multiplying both parts by 7.
- Find the missing number: \(\frac{2}{9} = \frac{?}{54}
- List three equivalent fractions for \(\frac{1}{4}\) using different multipliers.
- A recipe calls for \(\frac{3}{4}\) cup of flour. Find an equivalent fraction by multiplying both parts by 5.
- Find an equivalent fraction to \(\frac{7}{10}\) by multiplying both parts by 6.
1. \(\frac{5}{6} = \frac{15}{18}\) (multiply both by 3)
2. \(\frac{3}{8} = \frac{21}{56}\) (multiply both by 7)
3. The missing number is 12, so \(\frac{2}{9} = \frac{12}{54}\)
4. Three equivalent fractions: \(\frac{2}{8}, \frac{3}{12}, \frac{4}{16}\) (multiplied by 2, 3, and 4 respectively)
5. \(\frac{3}{4} = \frac{15}{20}\) (multiply both by 5)
6. \(\frac{7}{10} = \frac{42}{60}\) (multiply both by 6)