Fraction: A part of a whole represented as numerator/denominator
Numerator: Top number showing how many parts we have
Denominator: Bottom number showing total equal parts
Equivalent Fractions: Fractions with the same value but different numbers
- Visual Model Method: Draw pie charts or rectangles to compare
- Number Line Method: Place fractions on a number line
- Common Denominator Method: Convert to same denominator
- Cross Multiplication: Compare ad vs bc
When denominators are the same: Compare numerators. The fraction with the larger numerator is greater.
Visual Model:
\(\frac{3}{8}\) vs \(\frac{5}{8}\)
- Both fractions have the same denominator (8)
- Compare numerators: 3 vs 5
- Since 5 > 3, then \(\frac{5}{8} > \frac{3}{8}\)
\(\frac{3}{8}\) has denominator 8, \(\frac{5}{8}\) has denominator 8
3 vs 5 → 5 is greater than 3
When denominators are the same, the fraction with the larger numerator is greater
\(\frac{5}{8}\) is greater than \(\frac{3}{8}\)
• Same Denominator Rule: Compare numerators only
• Greater Than: 5 > 3, so \(\frac{5}{8} > \frac{3}{8}\)
• Visual Confirmation: More pieces shaded means larger fraction
When numerators are the same: Compare denominators. The fraction with the smaller denominator is greater.
Visual Model:
\(\frac{2}{3}\) vs \(\frac{2}{5}\)
- Both fractions have the same numerator (2)
- Compare denominators: 3 vs 5
- Since 3 < 5, then \(\frac{2}{3} > \frac{2}{5}\)
\(\frac{2}{3}\) has numerator 2, \(\frac{2}{5}\) has numerator 2
3 vs 5 → 3 is smaller than 5
When numerators are the same, the fraction with the smaller denominator is greater
\(\frac{2}{3}\) is greater than \(\frac{2}{5}\)
• Same Numerator Rule: Compare denominators only
• Smaller Denominator: Smaller denominator means larger pieces
• Visual Confirmation: Bigger slices mean larger fraction
Cross Multiplication: For \(\frac{a}{b}\) vs \(\frac{c}{d}\), compare \(a \times d\) vs \(b \times c\)
Visual Model:
\(\frac{3}{4}\) vs \(\frac{2}{3}\)
- Cross multiply: \(3 \times 3 = 9\) and \(4 \times 2 = 8\)
- Compare results: 9 vs 8
- Since 9 > 8, then \(\frac{3}{4} > \frac{2}{3}\)
\(3 \times 3 = 9\) and \(4 \times 2 = 8\)
9 vs 8 → 9 is greater than 8
Since \(3 \times 3 > 4 \times 2\), then \(\frac{3}{4} > \frac{2}{3}\)
\(\frac{3}{4}\) is greater than \(\frac{2}{3}\)
• Cross Multiplication: \(a \times d\) vs \(b \times c\)
• Comparison: Larger product indicates larger fraction
• Verification: Can convert to common denominator to confirm
Equivalent Fractions: Two fractions are equivalent if their cross products are equal.
Visual Model:
\(\frac{4}{6}\) vs \(\frac{2}{3}\)
- Cross multiply: \(4 \times 3 = 12\) and \(6 \times 2 = 12\)
- Compare results: 12 vs 12
- Since 12 = 12, then \(\frac{4}{6} = \frac{2}{3}\)
\(4 \times 3 = 12\) and \(6 \times 2 = 12\)
12 vs 12 → Products are equal
If cross products are equal, fractions are equivalent
\(\frac{4}{6} = \frac{4 \div 2}{6 \div 2} = \frac{2}{3}\)
Yes, \(\frac{4}{6}\) and \(\frac{2}{3}\) are equal (equivalent fractions)
• Equivalence Test: Cross products must be equal
• Simplification: Divide numerator and denominator by GCD
• Verification: Both methods confirm equivalence
Number Line Method: Plot fractions on a number line to compare their positions.
Number Line:
- Convert all fractions to have common denominators or decimals
- Find LCD of 2, 4, 4, 3 = 12
- Convert: \(\frac{1}{2} = \frac{6}{12}\), \(\frac{3}{4} = \frac{9}{12}\), \(\frac{1}{4} = \frac{3}{12}\), \(\frac{2}{3} = \frac{8}{12}\)
- Order by numerators: 3, 6, 8, 9
LCD of 2, 4, 4, 3 is 12
\(\frac{1}{2} = \frac{6}{12}\), \(\frac{3}{4} = \frac{9}{12}\), \(\frac{1}{4} = \frac{3}{12}\), \(\frac{2}{3} = \frac{8}{12}\)
3 < 6 < 8 < 9
\(\frac{3}{12} < \frac{6}{12} < \frac{8}{12} < \frac{9}{12}\)
\(\frac{1}{4} < \frac{1}{2} < \frac{2}{3} < \frac{3}{4}\)
From least to greatest: \(\frac{1}{4}, \frac{1}{2}, \frac{2}{3}, \frac{3}{4}\)
• Common Denominator: Convert to same denominator for easy comparison
• Ordering: Compare numerators once denominators are equal
• Verification: Number line confirms the order visually