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Finding the Fourth Proportional to 520.38, 780.49 and 155.09

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Solution

The fourth proportional to 520.38, 780.49 and 155.09 is: 232.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    520.38 : 780.49 = 155.09 : x
  2. Step 2: Convert to fraction form
    520.38/780.49 = 155.09/x
  3. Step 3: Cross multiply
    520.38x = 780.49 × 155.09
  4. Step 4: Simplify right side
    520.38x = 121,046.19
  5. Step 5: Solve for x
    x = 121,046.19/520.38
  6. Step 6: Final answer
    x = 232.61

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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.