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Finding the Fourth Proportional to 520.97, 782.47 and 405.65

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Solution

The fourth proportional to 520.97, 782.47 and 405.65 is: 609.27

Step by Step Solution

  1. Step 1: Write the proportion equation
    520.97 : 782.47 = 405.65 : x
  2. Step 2: Convert to fraction form
    520.97/782.47 = 405.65/x
  3. Step 3: Cross multiply
    520.97x = 782.47 × 405.65
  4. Step 4: Simplify right side
    520.97x = 317,408.96
  5. Step 5: Solve for x
    x = 317,408.96/520.97
  6. Step 6: Final answer
    x = 609.27

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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.