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Finding the Fourth Proportional to 490.54, 676.99 and 280.72

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Solution

The fourth proportional to 490.54, 676.99 and 280.72 is: 387.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    490.54 : 676.99 = 280.72 : x
  2. Step 2: Convert to fraction form
    490.54/676.99 = 280.72/x
  3. Step 3: Cross multiply
    490.54x = 676.99 × 280.72
  4. Step 4: Simplify right side
    490.54x = 190,044.63
  5. Step 5: Solve for x
    x = 190,044.63/490.54
  6. Step 6: Final answer
    x = 387.42

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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.