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Finding the Fourth Proportional to 490.20, 676.81 and 385.71

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Solution

The fourth proportional to 490.20, 676.81 and 385.71 is: 532.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    490.20 : 676.81 = 385.71 : x
  2. Step 2: Convert to fraction form
    490.20/676.81 = 385.71/x
  3. Step 3: Cross multiply
    490.20x = 676.81 × 385.71
  4. Step 4: Simplify right side
    490.20x = 261,052.39
  5. Step 5: Solve for x
    x = 261,052.39/490.20
  6. Step 6: Final answer
    x = 532.54

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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.