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Finding the Fourth Proportional to 628.03, 866.52 and 391.61

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Solution

The fourth proportional to 628.03, 866.52 and 391.61 is: 540.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    628.03 : 866.52 = 391.61 : x
  2. Step 2: Convert to fraction form
    628.03/866.52 = 391.61/x
  3. Step 3: Cross multiply
    628.03x = 866.52 × 391.61
  4. Step 4: Simplify right side
    628.03x = 339,337.90
  5. Step 5: Solve for x
    x = 339,337.90/628.03
  6. Step 6: Final answer
    x = 540.32

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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.