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Finding the Fourth Proportional to 640.72, 884.42 and 404.83

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Solution

The fourth proportional to 640.72, 884.42 and 404.83 is: 558.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.72 : 884.42 = 404.83 : x
  2. Step 2: Convert to fraction form
    640.72/884.42 = 404.83/x
  3. Step 3: Cross multiply
    640.72x = 884.42 × 404.83
  4. Step 4: Simplify right side
    640.72x = 358,039.75
  5. Step 5: Solve for x
    x = 358,039.75/640.72
  6. Step 6: Final answer
    x = 558.81

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.