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Finding the Fourth Proportional to 520.70, 781.00 and 439.16

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Solution

The fourth proportional to 520.70, 781.00 and 439.16 is: 658.69

Step by Step Solution

  1. Step 1: Write the proportion equation
    520.70 : 781.00 = 439.16 : x
  2. Step 2: Convert to fraction form
    520.70/781.00 = 439.16/x
  3. Step 3: Cross multiply
    520.70x = 781.00 × 439.16
  4. Step 4: Simplify right side
    520.70x = 342,978.96
  5. Step 5: Solve for x
    x = 342,978.96/520.70
  6. Step 6: Final answer
    x = 658.69

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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.