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Finding the Fourth Proportional to 490.66, 676.91 and 280.80

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Solution

The fourth proportional to 490.66, 676.91 and 280.80 is: 387.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    490.66 : 676.91 = 280.80 : x
  2. Step 2: Convert to fraction form
    490.66/676.91 = 280.80/x
  3. Step 3: Cross multiply
    490.66x = 676.91 × 280.80
  4. Step 4: Simplify right side
    490.66x = 190,076.33
  5. Step 5: Solve for x
    x = 190,076.33/490.66
  6. Step 6: Final answer
    x = 387.39

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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.