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Finding the Fourth Proportional to 627.70, 865.84 and 391.84

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Solution

The fourth proportional to 627.70, 865.84 and 391.84 is: 540.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    627.70 : 865.84 = 391.84 : x
  2. Step 2: Convert to fraction form
    627.70/865.84 = 391.84/x
  3. Step 3: Cross multiply
    627.70x = 865.84 × 391.84
  4. Step 4: Simplify right side
    627.70x = 339,268.34
  5. Step 5: Solve for x
    x = 339,268.34/627.70
  6. Step 6: Final answer
    x = 540.49

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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.