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Finding the Fourth Proportional to 520.87, 780.58 and 289.89

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Solution

The fourth proportional to 520.87, 780.58 and 289.89 is: 434.43

Step by Step Solution

  1. Step 1: Write the proportion equation
    520.87 : 780.58 = 289.89 : x
  2. Step 2: Convert to fraction form
    520.87/780.58 = 289.89/x
  3. Step 3: Cross multiply
    520.87x = 780.58 × 289.89
  4. Step 4: Simplify right side
    520.87x = 226,282.34
  5. Step 5: Solve for x
    x = 226,282.34/520.87
  6. Step 6: Final answer
    x = 434.43

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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.