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Finding the Fourth Proportional to 520.60, 781.42 and 406.30

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Solution

The fourth proportional to 520.60, 781.42 and 406.30 is: 609.86

Step by Step Solution

  1. Step 1: Write the proportion equation
    520.60 : 781.42 = 406.30 : x
  2. Step 2: Convert to fraction form
    520.60/781.42 = 406.30/x
  3. Step 3: Cross multiply
    520.60x = 781.42 × 406.30
  4. Step 4: Simplify right side
    520.60x = 317,490.95
  5. Step 5: Solve for x
    x = 317,490.95/520.60
  6. Step 6: Final answer
    x = 609.86

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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.