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Finding the Fourth Proportional to 80.62, 120.82 and 51.64

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Solution

The fourth proportional to 80.62, 120.82 and 51.64 is: 77.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    80.62 : 120.82 = 51.64 : x
  2. Step 2: Convert to fraction form
    80.62/120.82 = 51.64/x
  3. Step 3: Cross multiply
    80.62x = 120.82 × 51.64
  4. Step 4: Simplify right side
    80.62x = 6,238.89
  5. Step 5: Solve for x
    x = 6,238.89/80.62
  6. Step 6: Final answer
    x = 77.39

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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.