Fraction Multiplication: \(\frac{a}{b} \times \frac{c}{d} = \frac{a \times c}{b \times d}\)
Cross Simplification: Cancel common factors before multiplying
Proper vs Improper: Results may be proper or improper fractions
Mixed Numbers: Convert to improper fractions first
Section A: Basic fraction multiplication (5 questions)
Section B: Mixed numbers and whole numbers (3 questions)
Section C: Word problems (2 questions)
Section D: Advanced problems (2 questions)
Total: 12 questions, 50 points possible
Correct Answer: 4 points each
Partially Correct: 2 points each
Work Shown: 1 point each
Grading Scale: A(90-100%), B(80-89%), C(70-79%)
Read Carefully: Identify what's being multiplied
Check Work: Verify by estimation
Simplify: Always reduce to lowest terms
Time Management: 3 minutes per question
Section A: Basic Fraction Multiplication
\(\frac{2}{3} \times \frac{4}{5} = \frac{2 \times 4}{3 \times 5} = \frac{8}{15}\)
\(\frac{3}{4} \times \frac{1}{6} = \frac{3 \times 1}{4 \times 6} = \frac{3}{24} = \frac{1}{8}\)
\(\frac{5}{8} \times \frac{4}{10} = \frac{5 \times 4}{8 \times 10} = \frac{20}{80} = \frac{1}{4}\)
\(\frac{7}{9} \times \frac{3}{14} = \frac{7 \times 3}{9 \times 14} = \frac{21}{126} = \frac{1}{6}\)
\(\frac{2}{7} \times \frac{14}{15} = \frac{2 \times 14}{7 \times 15} = \frac{28}{105} = \frac{4}{15}\)
Section B: Mixed Numbers and Whole Numbers
\(\frac{3}{5} \times 4 = \frac{3}{5} \times \frac{4}{1} = \frac{3 \times 4}{5 \times 1} = \frac{12}{5} = 2\frac{2}{5}\)
\(2\frac{1}{3} = \frac{7}{3}\), so \(\frac{7}{3} \times \frac{3}{4} = \frac{7 \times 3}{3 \times 4} = \frac{21}{12} = 1\frac{3}{4}\)
\(3\frac{1}{2} = \frac{7}{2}\), so \(\frac{5}{6} \times \frac{7}{2} = \frac{5 \times 7}{6 \times 2} = \frac{35}{12} = 2\frac{11}{12}\)
Section C: Word Problems
\(\frac{3}{4} \times \frac{2}{3} = \frac{3 \times 2}{4 \times 3} = \frac{6}{12} = \frac{1}{2}\)
Emma ate \(\frac{1}{2}\) of the whole pizza.
\(\frac{2}{3} \times \frac{3}{4} = \frac{2 \times 3}{3 \times 4} = \frac{6}{12} = \frac{1}{2}\)
Tom should use \(\frac{1}{2}\) cup of sugar.
Section D: Advanced Problems
\(\frac{2}{3} \times \frac{4}{5} \times \frac{5}{8} = \frac{2 \times 4 \times 5}{3 \times 5 \times 8} = \frac{40}{120} = \frac{1}{3}\)
Notice that 5 in numerator and denominator cancels out.
If \(\frac{a}{b} \times \frac{b}{c} = \frac{2}{5}\) and \(\frac{b}{c} = \frac{3}{4}\), then:
\(\frac{a}{b} \times \frac{3}{4} = \frac{2}{5}\), so \(\frac{a}{b} = \frac{2}{5} \div \frac{3}{4} = \frac{2}{5} \times \frac{4}{3} = \frac{8}{15}\)
Step 1: Multiply numerators: \(2 \times 4 = 8\)
Step 2: Multiply denominators: \(3 \times 5 = 15\)
Step 3: Form result: \(\frac{8}{15}\)
Step 4: Check for simplification: GCD(8,15)=1, so already simplified
Final Answer: \(\frac{8}{15}\)
When multiplying fractions, multiply numerators together and denominators together.
Step 1: Multiply numerators: \(3 \times 1 = 3\)
Step 2: Multiply denominators: \(4 \times 6 = 24\)
Step 3: Form result: \(\frac{3}{24}\)
Step 4: Simplify: \(\frac{3}{24} = \frac{1}{8}\)
Alternative: Cross-simplify first: \(\frac{3}{4} \times \frac{1}{6} = \frac{1}{4} \times \frac{1}{2} = \frac{1}{8}\)
Final Answer: \(\frac{1}{8}\)
Always check for cross-simplification before multiplying to make calculations easier.
Step 1: Identify the fractions: Emma has \(\frac{3}{4}\) of pizza
Step 2: She eats \(\frac{2}{3}\) of what she has
Step 3: Set up multiplication: \(\frac{3}{4} \times \frac{2}{3}\)
Step 4: Cross-simplify: \(\frac{3}{4} \times \frac{2}{3} = \frac{1}{2} \times \frac{2}{1} = \frac{2}{2} = 1\)
Wait: Actually, \(\frac{3}{4} \times \frac{2}{3} = \frac{6}{12} = \frac{1}{2}\)
Final Answer: Emma ate \(\frac{1}{2}\) of the whole pizza
"Of" in word problems means multiply. Always interpret the context carefully.