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Finding the Fourth Proportional to 627.65, 865.98 and 391.50

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Solution

The fourth proportional to 627.65, 865.98 and 391.50 is: 540.16

Step by Step Solution

  1. Step 1: Write the proportion equation
    627.65 : 865.98 = 391.50 : x
  2. Step 2: Convert to fraction form
    627.65/865.98 = 391.50/x
  3. Step 3: Cross multiply
    627.65x = 865.98 × 391.50
  4. Step 4: Simplify right side
    627.65x = 339,031.17
  5. Step 5: Solve for x
    x = 339,031.17/627.65
  6. Step 6: Final answer
    x = 540.16

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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.