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Finding the Fourth Proportional to 80.20, 120.32 and 53.20

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Solution

The fourth proportional to 80.20, 120.32 and 53.20 is: 79.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    80.20 : 120.32 = 53.20 : x
  2. Step 2: Convert to fraction form
    80.20/120.32 = 53.20/x
  3. Step 3: Cross multiply
    80.20x = 120.32 × 53.20
  4. Step 4: Simplify right side
    80.20x = 6,401.02
  5. Step 5: Solve for x
    x = 6,401.02/80.20
  6. Step 6: Final answer
    x = 79.81

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.