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Finding the Fourth Proportional to 638.05, 880.33 and 385.87

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Solution

The fourth proportional to 638.05, 880.33 and 385.87 is: 532.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.05 : 880.33 = 385.87 : x
  2. Step 2: Convert to fraction form
    638.05/880.33 = 385.87/x
  3. Step 3: Cross multiply
    638.05x = 880.33 × 385.87
  4. Step 4: Simplify right side
    638.05x = 339,691.01
  5. Step 5: Solve for x
    x = 339,691.01/638.05
  6. Step 6: Final answer
    x = 532.39

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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.