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Finding the Fourth Proportional to 490.90, 676.96 and 397.58

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Solution

The fourth proportional to 490.90, 676.96 and 397.58 is: 548.27

Step by Step Solution

  1. Step 1: Write the proportion equation
    490.90 : 676.96 = 397.58 : x
  2. Step 2: Convert to fraction form
    490.90/676.96 = 397.58/x
  3. Step 3: Cross multiply
    490.90x = 676.96 × 397.58
  4. Step 4: Simplify right side
    490.90x = 269,145.76
  5. Step 5: Solve for x
    x = 269,145.76/490.90
  6. Step 6: Final answer
    x = 548.27

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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.