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Finding the Fourth Proportional to 657.52, 907.20 and 391.89

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Solution

The fourth proportional to 657.52, 907.20 and 391.89 is: 540.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    657.52 : 907.20 = 391.89 : x
  2. Step 2: Convert to fraction form
    657.52/907.20 = 391.89/x
  3. Step 3: Cross multiply
    657.52x = 907.20 × 391.89
  4. Step 4: Simplify right side
    657.52x = 355,522.61
  5. Step 5: Solve for x
    x = 355,522.61/657.52
  6. Step 6: Final answer
    x = 540.70

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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.