Compare Fractions 4/7 and 6/9: A Cake-Sharing Problem

Question

Benjamin ate 47 \frac{4}{7} of a cake and

George ate 69 \frac{6}{9} of the cake.

Who ate the most cake?

Video Solution

Step-by-Step Solution

To solve this problem, we'll compare the fractions representative of the cake portions that Benjamin and George ate.

  • Step 1: Simplify Fractions
    George ate 69 \frac{6}{9} of the cake. Simplifying this fraction, we divide both the numerator and the denominator by their greatest common divisor, which is 3. Thus, 69=23 \frac{6}{9} = \frac{2}{3} .
  • Step 2: Find Common Denominator
    The denominators of the two fractions we are comparing are 7 and 3. The least common multiple (LCM) of 7 and 3 is 21.
  • Step 3: Convert to Common Denominator
    Convert 47 \frac{4}{7} and 23 \frac{2}{3} to fractions with a common denominator of 21:
    - For 47 \frac{4}{7} , multiply the numerator and the denominator by 3: 47=4×37×3=1221 \frac{4}{7} = \frac{4 \times 3}{7 \times 3} = \frac{12}{21} .
    - For 23 \frac{2}{3} , multiply the numerator and the denominator by 7: 23=2×73×7=1421 \frac{2}{3} = \frac{2 \times 7}{3 \times 7} = \frac{14}{21} .
  • Step 4: Compare the Fractions
    Now, compare the numerators: 12 and 14. Since 14 is greater than 12, we can conclude that 1421 \frac{14}{21} (or 23 \frac{2}{3} ) is greater than 1221 \frac{12}{21} (or 47 \frac{4}{7} ).

Therefore, George ate more of the cake.

The correct answer is George.

Answer

George