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Finding the Fourth Proportional to 490.36, 676.21 and 420.66

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Solution

The fourth proportional to 490.36, 676.21 and 420.66 is: 580.09

Step by Step Solution

  1. Step 1: Write the proportion equation
    490.36 : 676.21 = 420.66 : x
  2. Step 2: Convert to fraction form
    490.36/676.21 = 420.66/x
  3. Step 3: Cross multiply
    490.36x = 676.21 × 420.66
  4. Step 4: Simplify right side
    490.36x = 284,454.50
  5. Step 5: Solve for x
    x = 284,454.50/490.36
  6. Step 6: Final answer
    x = 580.09

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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.