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Finding the Fourth Proportional to 658.29, 908.62 and 392.78

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Solution

The fourth proportional to 658.29, 908.62 and 392.78 is: 542.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    658.29 : 908.62 = 392.78 : x
  2. Step 2: Convert to fraction form
    658.29/908.62 = 392.78/x
  3. Step 3: Cross multiply
    658.29x = 908.62 × 392.78
  4. Step 4: Simplify right side
    658.29x = 356,889.05
  5. Step 5: Solve for x
    x = 356,889.05/658.29
  6. Step 6: Final answer
    x = 542.14

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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.